ORCID Profile
0000-0002-2375-3254
Current Organisations
Bangor University
,
University of the Sunshine Coast
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Public Health and Health Services | Aboriginal and Torres Strait Islander Health | Health Informatics | Aboriginal and Torres Strait Islander Information and Knowledge Systems | Archaeology | Environmental Biotechnology | Anthropology | Biological (Physical) Anthropology | Biodiscovery | Archaeological Science | Biological Control | Aboriginal and Torres Strait Islander Archaeology | Anthropological Genetics
Aboriginal and Torres Strait Islander Health - Determinants of Health | Aboriginal and Torres Strait Islander Education | Expanding Knowledge through Studies of Human Society | Understanding Australia's Past | Understanding Asia's Past | Conserving Aboriginal and Torres Strait Islander Heritage | Flora, Fauna and Biodiversity at Regional or Larger Scales |
Publisher: Oxford University Press (OUP)
Date: 04-2012
DOI: 10.1534/GENETICS.111.137893
Abstract: Here I show a gradual decline in the proportion of deleterious nonsynonymous SNPs (nSNPs) from tip to root of the human population tree. This study reveals that up to 48% of nSNPs specific to a single genome are deleterious in nature, which underscores the abundance of deleterious polymorphisms in humans.
Publisher: Oxford University Press (OUP)
Date: 2012
DOI: 10.1093/GBE/EVS092
Publisher: Oxford University Press (OUP)
Date: 08-10-2018
Publisher: Springer Science and Business Media LLC
Date: 18-04-2012
DOI: 10.1038/EJHG.2012.68
Publisher: Springer Science and Business Media LLC
Date: 28-06-2018
Publisher: Wiley
Date: 16-02-2018
Publisher: Frontiers Media SA
Date: 16-03-2023
Publisher: Proceedings of the National Academy of Sciences
Date: 06-06-2016
Abstract: This report is the first publication, to our knowledge, to report the complete mitochondrial genome of an ancient Aboriginal Australian. In addition, it also provides important evidence about the reliability of the only previous publication of this kind. The paper attained international significance, although its conclusions have remained controversial. Using second generation DNA sequencing methods, we provide strong evidence that the DNA sequences reported by Adcock et al. were, indeed, contamination. Our manuscript is also important, because the research was planned and conducted and is published with the support of the Barkindji, Ngiy aa, and Muthi Muthi indigenous groups.
Publisher: The Royal Society
Date: 23-12-2013
Abstract: Penguins are a remarkable group of birds, with the 18 extant species living in erse climatic zones from the tropics to Antarctica. The timing of the origin of these extant penguins remains controversial. Previous studies based on DNA sequences and fossil records have suggested widely differing times for the origin of the group. This has given rise to widely differing biogeographic narratives about their evolution. To resolve this problem, we sequenced five introns from 11 species representing all genera of living penguins. Using these data and other available DNA sequences, together with the ages of multiple penguin fossils to calibrate the molecular clock, we estimated the age of the most recent common ancestor of extant penguins to be 20.4 Myr (17.0–23.8 Myr). This time is half of the previous estimates based on molecular sequence data. Our results suggest that most of the major groups of extant penguins erged 11–16 Ma. This overlaps with the sharp decline in Antarctic temperatures that began approximately 12 Ma, suggesting a possible relationship between climate change and penguin evolution.
Publisher: Springer Science and Business Media LLC
Date: 07-2013
DOI: 10.1038/NCOMMS3071
Abstract: The ground tit (Parus humilis) is endemic to the Tibetan plateau. It is a member of family Paridae but it was long thought to be related to the ground jays because of their morphological similarities. Here we present the ground tit's genome and re-sequence two tits and one ground jay, to clarify this controversially taxonomic status and uncover its genetic adaptations to the Tibetan plateau. Our results show that ground tit groups with two tits and it erges from them between 7.7 and 9.9 Mya. Compared with other avian genomes, ground tit shows expansion in genes linked to energy metabolism and contractions in genes involved in immune and olfactory perception. We also found positively selected and rapidly evolving genes in hypoxia response and skeletal development. These results indicated that ground tit evolves basic strategies and 'tit-to-jay' change for coping with the life in an extreme environment.
Publisher: Oxford University Press (OUP)
Date: 03-2013
DOI: 10.1534/GENETICS.112.147900
Abstract: Previous studies observed a higher ratio of ergences at nonsynonymous and synonymous sites (ω = dN/dS) in species with a small population size compared to that estimated for those with a large population size. Here we examined the theoretical relationship between ω, effective population size (Ne), and selection coefficient (s). Our analysis revealed that when purifying selection is high, ω of species with small Ne is much higher than that of species with large Ne. However the difference between the two ω reduces with the decline in selection pressure (s → 0). We examined this relationship using primate and rodent genes and found that the ω estimated for highly constrained genes of primates was up to 2.9 times higher than that obtained for their orthologous rodent genes. Conversely, for genes under weak purifying selection the ω of primates was only 17% higher than that of rodents. When tissue specificity was used as a proxy for selection pressure we found that the ω of broadly expressed genes of primates was up to 2.1-fold higher than that of their rodent counterparts and this difference was only 27% for tissue specific genes. Since most of the nonsynonymous mutations in constrained or broadly expressed genes are deleterious, fixation of these mutations is influenced by Ne. This results in a higher ω of these genes in primates compared to those from rodents. Conversely, the majority of nonsynonymous mutations in less-constrained or tissue-specific genes are neutral or nearly neutral and therefore fixation of them is largely independent of Ne, which leads to the similarity of ω in primates and rodents.
Publisher: Informa UK Limited
Date: 24-10-2015
DOI: 10.3109/19401736.2013.840613
Abstract: Tuatara are the sister taxon to the Squamata (including lizards and snakes) and are regarded as the most distinctive surviving reptilian genus. They are currently inhabits on offshore islands around New Zealand and have been recognized as a species in need of active conservation management. In this study, we report a total number of five nearly complete mitochondrial genomes, which were sequenced by Sanger and Next Generation DNA sequencing methods. Our phylogenomic analysis revealed distinct clustering of tuatara populations from the north and south islands of New Zealand.
Publisher: Oxford University Press (OUP)
Date: 26-07-2006
Abstract: Although substantial and ecologically significant differences in elemental composition are well documented for whole organisms, little is known about whether such differences extend to lower levels of biological organization, such as the elemental composition of major molecules. In a proteome-scale investigation of 9 plant genomes and 9 animal genomes, we find that the nitrogen (N) content of plant proteins is lower than that in animal proteins. Furthermore, protein N content declines with the intensity of gene expression for plants, whereas the N content of animal proteins shows no consistent pattern with expression. Additional analyses indicate that the differences in N content between plant and animal proteomes and in plant proteins as a function of gene expression cannot be attributed to protein size, GC content, gene function, or amino acid properties. These patterns suggest that ecophysiological selection has operated to conserve N in plants via decreased reliance on N-rich amino acids. This inference was supported by an analysis of conserved and variable sites indicating that the N content of plant amino acids coded by variable sites is similar to that of the sites conserved between plant and animal genomes and shows no association with expression level. In contrast, in animals, the N content of amino acids coded by variable sites is significantly higher than that for conserved sites, suggesting relaxation of selective constraints for N usage in the animal lineage. This constitutes the first evidence for an influence of environmental resource availability on proteomes of multicellular organisms.
Publisher: Oxford University Press (OUP)
Date: 10-2019
Abstract: Wild abalone (Family Haliotidae) populations have been severely affected by commercial fishing, poaching, anthropogenic pollution, environment and climate changes. These issues have stimulated an increase in aquaculture production however production growth has been slow due to a lack of genetic knowledge and resources. We have sequenced a draft genome for the commercially important temperate Australian ‘greenlip’ abalone (Haliotis laevigata, Donovan 1808) and generated 11 tissue transcriptomes from a female adult abalone. Phylogenetic analysis of the greenlip abalone with reference to the Pacific abalone (Haliotis discus hannai) indicates that these abalone species erged approximately 71 million years ago. This study presents an in-depth analysis into the features of reproductive dysfunction, where we provide the putative biochemical messenger components (neuropeptides) that may regulate reproduction including gonad maturation and spawning. Indeed, we isolate the egg-laying hormone neuropeptide and under trial conditions induce spawning at 80% efficiency. Altogether, we provide a solid platform for further studies aimed at stimulating advances in abalone aquaculture production. The H. laevigata genome and resources are made available to the public on the abalone ‘omics website, abalonedb.org.
Publisher: Oxford University Press (OUP)
Date: 04-2008
DOI: 10.1534/GENETICS.107.086405
Abstract: Here I show that the mean codon usage bias of a genome, and of the lowly expressed genes in a genome, is largely similar across eukaryotes ranging from unicellular protists to vertebrates. Conversely, this bias in housekeeping genes and in highly expressed genes has a remarkable inverse relationship with species generation time that varies by more than four orders of magnitude. The relevance of these results to the nearly neutral theory of molecular evolution is discussed.
Publisher: Wiley
Date: 06-2012
DOI: 10.1111/J.1749-4877.2012.00288.X
Abstract: During the summer months, Adélie penguins represent the dominant biomass of terrestrial Antarctica. Literally millions of in iduals nest in ice-free areas around the coast of the continent. Hence, these modern populations of Adélie penguins have often been ch ioned as an ideal biological indicator of ecological and environmental changes that we currently face. In addition, Adélie penguins show an extraordinary record of sub-fossil remains, dating back to the late Pleistocene. At this time, temperatures were much lower than now. Hence, this species offers unique long-term information, at both the genomic and ecological levels, about how a species has responded to climate change over more than 40 000 years.
Publisher: SAGE Publications
Date: 10-06-2020
Publisher: Springer Science and Business Media LLC
Date: 13-10-2016
DOI: 10.1007/S00439-015-1604-Z
Abstract: Recent studies have shown that a high proportion of rare variants in European and African populations are deleterious in nature. However, the deleterious fraction of high-frequency variants is unclear. Using more than 6500 exomes we show a much higher fraction (11 %) of relatively high-frequency nonsynonymous (amino acid altering) variants (DAF 0.1–10 %) in European Americans (EA) compared to those from African Americans (AA). In contrast, this difference was only marginal (<2 %) for low-frequency nonsynonymous variants (DAF <0.1 %). Our results also revealed that the proportion of high-frequency deleterious nonsynonymous variants in EA was much higher (24 %) than that in AA and this difference was very small (4 %) for the low-frequency deleterious amino acid altering variants. We also show that EA have significantly more number of high-frequency deleterious nonsynonymous variants per genome than AA. The high proportion of high-frequency deleterious variants in EA could be the result of the well-known bottleneck experienced by European populations in which harmful mutations may have drifted to high frequencies. The estimated ages of deleterious variants support this prediction. Our results suggest that high-frequency variants could be relatively more likely to be associated with diseases in Europeans than in Africans and hence emphasize the need for population-specific strategies in genomic medicine studies.
Publisher: Elsevier BV
Date: 07-2008
DOI: 10.1016/J.TREE.2008.04.002
Abstract: Ancient DNA research is on the crest of a 'third wave' of progress due to the introduction of a new generation of DNA sequencing technologies. Here we review the advantages and disadvantages of the four new DNA sequencers that are becoming available to researchers. These machines now allow the recovery of orders of magnitude more DNA sequence data, albeit as short sequence reads. Hence, the potential reassembly of complete ancient genomes seems imminent, and when used to screen libraries of ancient sequences, these methods are cost effective. This new wealth of data is also likely to herald investigations into the functional properties of extinct genes and gene complexes and will improve our understanding of the biological basis of extinct phenotypes.
Publisher: Public Library of Science (PLoS)
Date: 13-11-2019
Publisher: Springer Science and Business Media LLC
Date: 2002
Abstract: Comparative analysis of RNA sequences is the basis for the detailed and accurate predictions of RNA structure and the determination of phylogenetic relationships for organisms that span the entire phylogenetic tree. Underlying these accomplishments are very large, well-organized, and processed collections of RNA sequences. This data, starting with the sequences organized into a database management system and aligned to reveal their higher-order structure, and patterns of conservation and variation for organisms that span the phylogenetic tree, has been collected and analyzed. This type of information can be fundamental for and have an influence on the study of phylogenetic relationships, RNA structure, and the melding of these two fields. We have prepared a large web site that disseminates our comparative sequence and structure models and data. The four major types of comparative information and systems available for the three ribosomal RNAs (5S, 16S, and 23S rRNA), transfer RNA (tRNA), and two of the catalytic intron RNAs (group I and group II) are: (1) Current Comparative Structure Models (2) Nucleotide Frequency and Conservation Information (3) Sequence and Structure Data and (4) Data Access Systems. This online RNA sequence and structure information, the result of extensive analysis, interpretation, data collection, and computer program and web development, is accessible at our Comparative RNA Web (CRW) Site www.rna.icmb.utexas.edu. In the future, more data and information will be added to these existing categories, new categories will be developed, and additional RNAs will be studied and presented at the CRW Site.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 07-12-2018
Abstract: Ancient DNA facilitates the return of remains to Indigenous tribal groups, resolving a long-standing concern.
Publisher: Oxford University Press (OUP)
Date: 2011
DOI: 10.1093/GBE/EVR108
Publisher: Springer Science and Business Media LLC
Date: 25-04-2023
Publisher: The Royal Society
Date: 19-01-2015
Abstract: Recently, the study of ancient DNA (aDNA) has been greatly enhanced by the development of second-generation DNA sequencing technologies and targeted enrichment strategies. These developments have allowed the recovery of several complete ancient genomes, a result that would have been considered virtually impossible only a decade ago. Prior to these developments, aDNA research was largely focused on the recovery of short DNA sequences and their use in the study of phylogenetic relationships, molecular rates, species identification and population structure. However, it is now possible to sequence a large number of modern and ancient complete genomes from a single species and thereby study the genomic patterns of evolutionary change over time. Such a study would herald the beginnings of ancient population genomics and its use in the study of evolution. Species that are amenable to such large-scale studies warrant increased research effort. We report here progress on a population genomic study of the Adélie penguin ( Pygoscelis adeliae ). This species is ideally suited to ancient population genomic research because both modern and ancient s les are abundant in the permafrost conditions of Antarctica. This species will enable us to directly address many of the fundamental questions in ecology and evolution.
Publisher: Cold Spring Harbor Laboratory
Date: 16-04-2019
DOI: 10.1101/610584
Abstract: The ancient catacombs of Egypt harbor millions of well-preserved mummified Sacred Ibis ( Threskiornis aethiopicus ) dating from ∼600BC. Although it is known that a very large number of these ‘votive’ mummies were sacrificed to the Egyptian God Thoth, how the ancient Egyptians obtained millions of these birds for mummification remains unresolved. Ancient Egyptian textual evidences suggest they may have been raised in dedicated large-scale farms. To investigate the most likely method used by the priests to secure birds for mummification, we report the first study of complete mitochondrial genomes of 14 Sacred Ibis mummies interred ∼2500 years ago. We analysed and compared the mitogenomic ersity among Sacred Ibis mummies to that found in modern Sacred Ibis populations from throughout Africa. The ancient birds show a high level of genetic variation comparable to that identified in modern African populations, contrary to the suggestion in ancient hieroglyphics (or ancient writings) of centralized industrial scale farming of sacrificial birds. This suggests a sustained short-term taming of the wild Sacred Ibis for the ritual yearly demand.
Publisher: Springer Science and Business Media LLC
Date: 12-2019
DOI: 10.1186/S12863-019-0798-9
Abstract: It is well known that the effective size of a population ( N e ) is one of the major determinants of the amount of genetic variation within the population. However, it is unclear whether the types of genetic variations are also dictated by the effective population size. To examine this, we obtained whole genome data from over 100 populations of the world and investigated the patterns of mutational changes. Our results revealed that for low frequency variants, the ratio of AT→GC to GC→AT variants ( β ) was similar across populations, suggesting the similarity of the pattern of mutation in various populations. However, for high frequency variants, β showed a positive correlation with the effective population size of the populations. This suggests a much higher proportion of high frequency AT→GC variants in large populations (e.g. Africans) compared to those with small population sizes (e.g. Asians). These results imply that the substitution patterns vary significantly between populations. These findings could be explained by the effect of GC-biased gene conversion (gBGC), which favors the fixation of G/C over A/T variants in populations. In large population, gBGC causes high β . However, in small populations, genetic drift reduces the effect of gBGC resulting in reduced β . This was further confirmed by a positive relationship between N e and β for homozygous variants. Our results highlight the huge variation in the types of homozygous and high frequency polymorphisms between world populations. We observed the same pattern for deleterious variants, implying that the homozygous polymorphisms associated with recessive genetic diseases will be more enriched with G or C in populations with large N e (e.g. Africans) than in populations with small N e (e.g. Europeans).
Publisher: Elsevier BV
Date: 11-2009
DOI: 10.1016/J.TIG.2009.09.005
Abstract: Using entire modern and ancient mitochondrial genomes of Adélie penguins (Pygoscelis adeliae) that are up to 44000 years old, we show that the rates of evolution of the mitochondrial genome are two to six times greater than those estimated from phylogenetic comparisons. Although the rate of evolution at constrained sites, including nonsynonymous positions and RNAs, varies more than twofold with time (between shallow and deep nodes), the rate of evolution at synonymous sites remains the same. The time-independent neutral evolutionary rates reported here would be useful for the study of recent evolutionary events.
Publisher: Springer Science and Business Media LLC
Date: 12-2010
Abstract: Kiwi is a highly distinctive, flightless and endangered ratite bird endemic to New Zealand. To understand the patterns of molecular evolution of the nuclear protein-coding genes in brown kiwi ( Apteryx australis mantelli ) and to determine the timescale of avian history we sequenced a transcriptome obtained from a kiwi embryo using next generation sequencing methods. We then assembled the conserved protein-coding regions using the chicken proteome as a scaffold. Using 1,543 conserved protein coding genes we estimated the neutral evolutionary ergence between the kiwi and chicken to be ~45%, which is approximately equal to the ergence computed for the human-mouse pair using the same set of genes. A large fraction of genes was found to be under high selective constraint, as most of the expressed genes appeared to be involved in developmental gene regulation. Our study suggests a significant relationship between gene expression levels and protein evolution. Using sequences from over 700 nuclear genes we estimated the ergence between the two basal avian groups, Palaeognathae and Neognathae to be 132 million years, which is consistent with previous studies using mitochondrial genes. The results of this investigation revealed patterns of mutation and purifying selection in conserved protein coding regions in birds. Furthermore this study suggests a relatively cost-effective way of obtaining a glimpse into the fundamental molecular evolutionary attributes of a genome, particularly when no closely related genomic sequence is available.
Publisher: PeerJ
Date: 06-12-2019
DOI: 10.7717/PEERJ.8213
Abstract: In the past decades a number of software programs have been developed to infer phylogenetic relationships between populations. However, most of these programs typically use alignments of sequences from genes to build phylogeny. Recently, many standalone or web applications have been developed to handle large-scale whole genome data, but they are either computationally intensive, dependent on third party software or required significant time and resource of a web server. In the post-genomic era, researchers are able to obtain bioinformatically processed high-quality publication-ready whole genome data for many in iduals in a population from next generation sequencing companies due to the reduction in the cost of sequencing and analysis. Such genotype data is typically presented in the Variant Call Format (VCF) and there is no simple software available that directly uses this data format to construct the phylogeny of populations in a short time. To address this limitation, we have developed a user-friendly software, VCF2PopTree that uses genome-wide SNPs to construct and display phylogenetic trees in seconds to minutes. For ex le, it reads a VCF file containing 4 million SNPs and draws a tree in less than 30 seconds. VCF2PopTree accepts genotype data from a local machine, constructs a tree using UPGMA and Neighbour-Joining algorithms and displays it on a web-browser. It also produces pairwise- ersity matrix in MEGA and PHYLIP file formats as well as trees in the Newick format which could be directly used by other popular phylogenetic software programs. The software including the source code, a test VCF file and a documentation are available at: ansubs/vcf2pop .
Publisher: Elsevier BV
Date: 03-2008
DOI: 10.1016/J.TIG.2007.12.002
Abstract: The tuatara of New Zealand is a unique reptile that coexisted with dinosaurs and has changed little morphologically from its Cretaceous relatives. Tuatara have very slow metabolic and growth rates, long generation times and slow rates of reproduction. This suggests that the species is likely to exhibit a very slow rate of molecular evolution. Our analysis of ancient and modern tuatara DNA shows that, surprisingly, tuatara have the highest rate of molecular change recorded in vertebrates. Our work also suggests that rates of neutral molecular and phenotypic evolution are decoupled.
Publisher: Wiley
Date: 14-03-2008
Publisher: Elsevier BV
Date: 2009
Publisher: Wiley
Date: 09-2023
DOI: 10.1002/ECE3.10525
Publisher: Springer Science and Business Media LLC
Date: 12-2006
Publisher: Springer Science and Business Media LLC
Date: 20-02-2016
Publisher: Cold Spring Harbor Laboratory
Date: 05-2003
DOI: 10.1101/GR.1152803
Abstract: Point mutation rates in exons (synonymous sites) and noncoding (introns and intergenic) regions are generally assumed to be the same. However, comparative sequence analyses of synonymous substitutions in exons (81 genes) and that of long intergenic fragments (141.3 kbp) of human and chimpanzee genomes reveal a 30%–60% higher mutation rate in exons than in noncoding DNA. We propose a differential CpG content hypothesis to explain this fundamental, and seemingly unintuitive, pattern. We find that the increased exonic rate is the result of the relative overabundance of synonymous sites involved in CpG dinucleotides, as the evolutionary ergence in non-CpG sites is similar in noncoding DNA and synonymous sites of exons. Expectations and predictions of our hypothesis are confirmed in comparisons involving more distantly related species, including human–orangutan, human–baboon, and human–macaque. Our results suggest an underlying mechanism for higher mutation rate in GC-rich genomic regions, predict nonlinear accumulation of mutations in pseudogenes over time, and provide a possible explanation for the observed higher ersity of single nucleotide polymorphisms (SNPs) in the synonymous sites of exons compared to the noncoding regions.
Publisher: Oxford University Press (OUP)
Date: 06-01-2009
Abstract: Mildly deleterious mutations initially contribute to the ersity of a population, but later they are selected against at high frequency and are eliminated eventually. Using over 1,500 complete human mitochondrial genomes along with those of Neanderthal and Chimpanzee, I provide empirical evidence for this prediction by tracing the footprints of natural selection over time. The results show a highly significant inverse relationship between the ratio of nonsynonymous-to-synonymous ergence (d(N)/d(S)) and the age of human haplogroups. Furthermore, this study suggests that slightly deleterious mutations constitute up to 80% of the mitochondrial amino acid replacement mutations detected in human populations and that over the last 500,000 years these mutations have been gradually removed.
Publisher: Springer Science and Business Media LLC
Date: 02-07-2021
DOI: 10.1007/S00415-021-10665-9
Abstract: We studied the prevalence of neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) in Indigenous populations of Australia and New Zealand with the aim of assessing potential differences. Cases of possible NMOSD and MS were collected from Australia and New Zealand. Clinical details, MR imaging, and serologic results were used to apply 2015 IPND diagnostic criteria for NMOSD and 2010 McDonald criteria for MS. Frequencies of self-determined ethnic ancestry were calculated for confirmed NMOSD, suspected NMOSD, and MS. Prevalence rates for NMOSD and MS according to ancestry were compared. There were 75 cases with NMOSD, 89 with suspected NMSOD, and 101 with MS. NMOSD cases were more likely to have Asian, Indigenous, or Other ancestry compared to suspected NMOSD or MS. There were no differences in the clinical phenotype of NMOSD seen in Indigenous compared to European ancestry populations. Per 100,000, the prevalence estimate for NMOSD in people with Māori ancestry was 1.50 (95% CI 0.52-2.49) which was similar to those with Asian ancestry 1.57 (95% CI 1.15-1.98). NMOSD prevalence in Australian Aboriginal and Torres Strait Islander populations was 0.38 (95% CI 0.00-0.80) per 100,000. The prevalence of NMOSD in the Māori population is similar to South East Asian countries, reflecting their historical origins. The prevalence of MS in this group is intermediate between those with South East Asian and European ancestry living in New Zealand. Both NMOSD and particularly MS appear to be uncommon in the Indigenous populations of Australia.
Publisher: Springer Science and Business Media LLC
Date: 03-03-2015
DOI: 10.1038/SREP08703
Abstract: Population genetic models predict that populations that are geographically close to each other are expected to be genetically more similar to each other compared to those that are widely separate. However the patterns of relationships between geographic distance and molecular ergences at neutral and constrained regions of the genome are unclear. We attempted to clarify this relationship by sequencing complete mitochondrial genomes of the relic species Tuatara ( Sphenodon punctatus ) from ten offshore islands of New Zealand. We observed a positive relationship that showed a proportional increase in the neutral ersity at synonymous sites (dS), with increasing geographical distance. In contrast we showed that ersity at evolutionarily constrained sites (dC) was elevated in the case of comparisons involving closely located populations. Conversely ersity was reduced in the case of comparisons between distantly located populations. These patterns were confirmed by a significant negative relationship between the ratio of dC/dS and geographic distance. The observed high dC/dS could be explained by the abundance of deleterious mutations in comparisons involving closely located populations, due to the recent population ergence times. Since distantly related populations were separated over long periods of time, deleterious mutations might have been removed by purifying selection.
Publisher: Springer Science and Business Media LLC
Date: 27-06-2021
DOI: 10.1186/S13104-021-05664-Y
Abstract: Domestication of wild animals results in a reduction in the effective population size, and this could affect the deleterious mutation load of domesticated breeds. Furthermore, artificial selection will also contribute to the accumulation of deleterious mutations due to the increased rate of inbreeding among these animals. The process of domestication, founder population size, and artificial selection differ between cattle breeds, which could lead to a variation in their deleterious mutation loads. We investigated this using mitochondrial genome data from 364 animals belonging to 18 cattle breeds of the world. Our analysis revealed more than a fivefold difference in the deleterious mutation load among cattle breeds. We also observed a negative correlation between the breed age and the proportion of deleterious amino acid-changing polymorphisms. This suggests a proportionally higher deleterious SNPs in young breeds compared to older breeds. Our results highlight the magnitude of difference in the deleterious mutations present in the mitochondrial genomes of various breeds. The results of this study could be useful in predicting the rate of incidence of genetic diseases in different breeds.
Publisher: Cold Spring Harbor Laboratory
Date: 28-11-2022
DOI: 10.1101/2022.11.28.518181
Abstract: At the end of the last ice age, several Atlantic salmon populations got caught up in the lakes and other small waterbodies of the Northern Hemisphere. Therefore, the pattern of evolution shaping the landlocked salmon populations is different from the other anadromous salmons, which migrate between the sea and rivers. According to the theories of population genetics, the effect of genetic drift is expected to be more pronounced in the former compared to the latter. Here we examined this using the whole genome data of landlocked and anadromous salmon populations of Norway. Our results showed a 50-80% reduction in the genomic heterozygosity in the landlocked compared to anadromous salmon populations. The number and total size of the runs of homozygosity (RoH) segments of landlocked salmons were 2 to 8-fold higher than those of their anadromous counterparts. We found the former had a higher ratio of nonsynonymous-to-synonymous ersities than the latter. The investigation also revealed a significant elevation of homozygous deleterious Single Nucleotide Variants (SNVs) in the landlocked salmon compared to the anadromous populations. All these results point to a significant reduction in the population size of the landlocked salmons, which might have started after the last glacial epoch. Previous studies on terrestrial vertebrates observed similar signatures of a bottleneck when the populations from Island and the mainland were compared. Since landlocked waterbody such as ponds and lakes are geographically analogous to Islands for fish populations, the findings of this study suggest the similarity in the patterns of evolution between the two.
Publisher: Oxford University Press (OUP)
Date: 30-08-2006
Publisher: Wiley
Date: 07-2019
DOI: 10.1002/BES2.1551
Publisher: Oxford University Press (OUP)
Date: 31-10-2003
Publisher: Elsevier BV
Date: 11-2003
DOI: 10.1016/J.VIROL.2003.08.001
Abstract: Disease is among the suspected causes of hibian population declines, and an iridovirus and a chytrid fungus are the primary pathogens associated with hibian mortalities. Ambystoma tigrinum virus (ATV) and a closely related strain, Regina ranavirus (RRV), are implicated in salamander die-offs in Arizona and Canada, respectively. We report the complete sequence of the ATV genome and partial sequence of the RRV genome. Sequence analysis of the ATV/RRV genomes showed marked similarity to other ranaviruses, including tiger frog virus (TFV) and frog virus 3 (FV3), the type virus of the genus Ranavirus (family Iridoviridae), as well as more distant relationships to lymphocystis disease virus, Chilo iridescent virus, and infectious spleen and kidney necrosis virus. Putative open reading frames (ORFs) in the ATV sequence identified 24 genes that appear to control virus replication and block antiviral responses. In addition, >50 other putative genes, homologous to ORFs in other iridoviral genomes but of unknown function, were also identified. Sequence comparison performed by dot plot analysis between ATV and itself revealed a conserved 14-bp palindromic repeat within most intragenic regions. Dot plot analysis of ATV vs RRV sequences identified several polymorphisms between the two isolates. Finally, a comparison of ATV and TFV genomic sequences identified genomic rearrangements consistent with the high recombination frequency of iridoviruses. Given the adverse effects that ranavirus infections have on hibian and fish populations, ATV/RRV sequence information will allow the design of better diagnostic probes for identifying ranavirus infections and extend our understanding of molecular events in ranavirus-infected cells.
Publisher: Oxford University Press (OUP)
Date: 04-10-2015
DOI: 10.1093/BIOINFORMATICS/BTU653
Abstract: Motivation: A codon position could perform different or multiple roles in alternative transcripts of a gene. For instance, a non-synonymous position in one transcript could be a synonymous site in another. Alternatively, a position could remain as non-synonymous in multiple transcripts. Here we examined the impact of codon position plurality on the frequency of deleterious single-nucleotide variations (SNVs) using data from 6500 human exomes. Results: Our results showed that the proportion of deleterious SNVs was more than 2-fold higher in positions that remain non-synonymous in multiple transcripts compared with that observed in positions that are non-synonymous in one or some transcript(s) and synonymous or intronic in other(s). Furthermore, we observed a positive relationship between the fraction of deleterious non-synonymous SNVs and the number of proteins (alternative splice variants) affected. These results demonstrate that the plurality of codon positions is an important attribute, which could be useful in identifying mutations associated with diseases. Contact: s.subramanian@griffith.edu.au Supplementary Information: Supplementary data are available at Bioinformatics online
Publisher: Oxford University Press (OUP)
Date: 25-04-2003
Publisher: Springer Science and Business Media LLC
Date: 15-10-2021
DOI: 10.1186/S12711-021-00674-7
Abstract: The domestication of wild animals has resulted in a reduction in effective population sizes, which can affect the deleterious mutation load of domesticated breeds. In addition, artificial selection contributes to the accumulation of deleterious mutations because of an increased rate of inbreeding among domesticated animals. Since founder population sizes and artificial selection differ between cattle breeds, their deleterious mutation load can vary. We investigated this question by using whole-genome data from 432 animals belonging to 54 worldwide cattle breeds. Our analysis revealed a negative correlation between genomic heterozygosity and nonsynonymous-to-silent ersity ratio, which suggests a higher proportion of single nucleotide variants (SNVs) affecting proteins in low- ersity breeds. Our results also showed that low- ersity breeds had a larger number of high-frequency (derived allele frequency (DAF) 0.51) deleterious SNVs than high- ersity breeds. An opposite trend was observed for the low-frequency (DAF ≤ 0.51) deleterious SNVs. Overall, the number of high-frequency deleterious SNVs was larger in the genomes of taurine cattle breeds than of indicine breeds, whereas the number of low-frequency deleterious SNVs was larger in the genomes of indicine cattle than in those of taurine cattle. Furthermore, we observed significant variation in the counts of deleterious SNVs within taurine breeds. The variations in deleterious mutation load between taurine and indicine breeds could be attributed to the population sizes of the wild progenitors before domestication, whereas the variations observed within taurine breeds could be due to differences in inbreeding level, strength of artificial selection, and/or founding population size. Our findings imply that the incidence of genetic diseases can vary between cattle breeds.
Publisher: Oxford University Press (OUP)
Date: 09-2004
DOI: 10.1534/GENETICS.104.028944
Abstract: Natural selection leaves its footprints on protein-coding sequences by modulating their silent and replacement evolutionary rates. In highly expressed genes in invertebrates, these footprints are seen in the higher codon usage bias and lower synonymous ergence. In mammals, the highly expressed genes have a shorter gene length in the genome and the breadth of expression is known to constrain the rate of protein evolution. Here we have examined how the rates of evolution of proteins encoded by the vertebrate genomes are modulated by the amount (intensity) of gene expression. To understand how natural selection operates on proteins that appear to have arisen in earlier and later phases of animal evolution, we have contrasted patterns of mouse proteins that have homologs in invertebrate and protist genomes (Precambrian genes) with those that do not have such detectable homologs (vertebrate-specific genes). We find that the intensity of gene expression relates inversely to the rate of protein sequence evolution on a genomic scale. The most highly expressed genes actually show the lowest total number of substitutions per polypeptide, consistent with cumulative effects of purifying selection on in idual amino acid replacements. Precambrian genes exhibit a more pronounced difference in protein evolutionary rates (up to three times) between the genes with high and low expression levels as compared to the vertebrate-specific genes, which appears to be due to the narrower breadth of expression of the vertebrate-specific genes. These results provide insights into the differential relationship and effect of the increasing complexity of animal body form on evolutionary rates of proteins.
Publisher: MDPI AG
Date: 22-01-2022
Abstract: Estimating the extent of genetic differentiation between populations is an important measure in population genetics, ecology and evolutionary biology. The fixation index, or FST, is an important measure, which is routinely used to quantify this. Previous studies have shown that the FST estimated for selectively constrained regions was significantly lower than that estimated for neutral regions. By deriving the theoretical relationship between FST at neutral and constrained sites, we show that excess in the fraction of deleterious variations segregating within populations compared to those segregating between populations is the cause for the reduction in FST estimated at constrained sites. Using whole-genome data, our results revealed that the magnitude of reduction in FST estimates obtained for selectively constrained regions was much higher for distantly related populations compared to those estimated for closely related pairs. For ex le, the reduction was 47% for comparison between Europeans and Africans, 30% for the European and Asian comparison, 16% for the Northern and Southern European pair, and only 4% for the comparison involving two Southern European (Italian and Spanish) populations. Since deleterious variants are purged over time due to purifying selection, their contribution to the among-population ersity at constrained sites decreases with the increase in the ergence between populations. However, within-population ersities remain the same for all pairs compared therefore, the FST estimated at constrained sites for distantly related populations are much smaller than those estimated for closely related populations. We obtained similar results when only the SNPs with similar allele frequencies at neutral and constrained sites were used. Our results suggest that the level of population ergence should be considered when comparing constrained site FST estimates from different pairs of populations.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 12-12-2014
Abstract: To better determine the history of modern birds, we performed a genome-scale phylogenetic analysis of 48 species representing all orders of Neoaves using phylogenomic methods created to handle genome-scale data. We recovered a highly resolved tree that confirms previously controversial sister or close relationships. We identified the first ergence in Neoaves, two groups we named Passerea and Columbea, representing independent lineages of erse and convergently evolved land and water bird species. Among Passerea, we infer the common ancestor of core landbirds to have been an apex predator and confirm independent gains of vocal learning. Among Columbea, we identify pigeons and flamingoes as belonging to sister clades. Even with whole genomes, some of the earliest branches in Neoaves proved challenging to resolve, which was best explained by massive protein-coding sequence convergence and high levels of incomplete lineage sorting that occurred during a rapid radiation after the Cretaceous-Paleogene mass extinction event about 66 million years ago.
Publisher: Proceedings of the National Academy of Sciences
Date: 15-01-2002
Abstract: Knowledge of the rate of point mutation is of fundamental importance, because mutations are a vital source of genetic novelty and a significant cause of human diseases. Currently, mutation rate is thought to vary many fold among genes within a genome and among lineages in mammals. We have conducted a computational analysis of 5,669 genes (17,208 sequences) from species representing major groups of placental mammals to characterize the extent of mutation rate differences among genes in a genome and among erse mammalian lineages. We find that mutation rate is approximately constant per year and largely similar among genes. Similarity of mutation rates among lineages with vastly different generation lengths and physiological attributes points to a much greater contribution of replication-independent mutational processes to the overall mutation rate. Our results suggest that the average mammalian genome mutation rate is 2.2 × 10 −9 per base pair per year, which provides further opportunities for estimating species and population ergence times by using molecular clocks.
Publisher: Oxford University Press (OUP)
Date: 21-02-2018
DOI: 10.1093/GBE/EVY047
Publisher: Springer Science and Business Media LLC
Date: 21-09-2016
DOI: 10.1038/NATURE18299
Abstract: The population history of Aboriginal Australians remains largely uncharacterized. Here we generate high-coverage genomes for 83 Aboriginal Australians (speakers of Pama-Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors ersified 25-40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10-32 kya. We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama-Nyungan languages. We estimate that Aboriginal Australians and Papuans erged from Eurasians 51-72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert.
Publisher: Informa UK Limited
Date: 24-06-2014
DOI: 10.3109/19401736.2013.800503
Abstract: The complete mitochondrial genome of the Chinstrap penguin (Pygoscelis antarcticus) was sequenced and compared with other penguin mitogenomes. The genome is 15,972 bp in length with the number and order of protein coding genes and RNAs being very similar to that of other known penguin mitogenomes. Comparative nucleotide analysis showed the Chinstrap mitogenome shares 94% homology with the mitogenome of its sister species, Pygoscelis adelie (Adélie penguin). Divergence at nonsynonymous nucleotide positions was found to be up to 23 times less than that observed in synonymous positions of protein coding genes, suggesting high selection constraints. The complete mitogenome data will be useful for genetic and evolutionary studies of penguins.
Publisher: Oxford University Press (OUP)
Date: 15-04-2011
Abstract: Deleterious mutations associated with human diseases are predominantly found in conserved positions and positions that are essential for the structure and/or function of proteins. However, these mutations are purged from the human population over time and prevented from being fixed. Contrary to this belief, here I show that high proportions of deleterious amino acid changing mutations are fixed at positions critical for the structure and/or function of proteins. Similarly, a high rate of fixation of deleterious mutations was observed in slow-evolving amino acid positions of human proteins. The fraction of deleterious substitutions was found to be two times higher in relatively conserved amino acid positions than in highly variable positions. This study also found fixation of a much higher proportion of radical amino acid changes in primates compared with rodents and artiodactyls in slow-evolving positions. Previous studies observed a higher proportion of nonsynonymous substitutions in humans compared with other mammals, which was taken as indirect evidence for the fixation of deleterious mutations in humans. However, the results of this investigation provide direct evidence for this prediction by suggesting that the excess nonsynonymous mutations fixed in humans are indeed deleterious in nature. Furthermore, these results suggest that studies on disease-associated mutations should consider that a significant fraction of such deleterious mutations has already been fixed in the human genome, and thus, the effects of new mutations at those amino acid positions may not necessarily be deleterious and might even result in reversion to benign phenotypes.
Publisher: MDPI AG
Date: 12-01-2021
Abstract: Recent studies suggested that the fraction of CG dinucleotides (CpG) is severely reduced in the genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The CpG deficiency was predicted to be the adaptive response of the virus to evade degradation of the viral RNA by the antiviral zinc finger protein that specifically binds to CpG nucleotides. By comparing all representative genomes belonging to the genus Betacoronavirus, this study examined the potential time of origin of CpG depletion. The results of this investigation revealed a highly significant correlation between the proportions of CpG nucleotide (CpG content) of the betacoronavirus species and their times of ergence from SARS-CoV-2. Species that are distantly related to SARS-CoV-2 had much higher CpG contents than that of SARS-CoV-2. Conversely, closely related species had low CpG contents that are similar to or slightly higher than that of SARS-CoV-2. These results suggest a systematic and continuous reduction in the CpG content in the SARS-CoV-2 lineage that might have started since the Sarbecovirus + Hibecovirus clade separated from Nobecovirus, which was estimated to be 1213 years ago. This depletion was not found to be mediated by the GC contents of the genomes. Our results also showed that the depletion of CpG occurred at neutral positions of the genome as well as those under selection. The latter is evident from the progressive reduction in the proportion of arginine amino acid (coded by CpG dinucleotides) in the SARS-CoV-2 lineage over time. The results of this study suggest that shedding CpG nucleotides from their genome is a continuing process in this viral lineage, potentially to escape from their host defense mechanisms.
Publisher: Oxford University Press (OUP)
Date: 25-10-2009
Abstract: Previous studies on human mitochondrial genomes showed that the ratio of intra-specific ersities at nonsynonymous-to-synonymous positions was two to ten times higher than the ratio of interspecific ergences at these positions, suggesting an excess of slightly deleterious nonsynonymous polymorphisms. However, such an overabundance of nonsynonymous single nucleotide polymorphisms (SNPs) was not found in human nuclear genomes. Here, genome-wide estimates using >14,000 human-chimp nuclear genes and 1 million SNPs from four human genomes showed a significant proportion of deleterious nonsynonymous SNPs (∼ 15%). Importantly, this study reveals a negative correlation between the magnitude of selection pressure and the proportion of deleterious SNPs on human genes. The proportion of deleterious amino acid replacement polymorphisms is 3.5 times higher in genes under high purifying selection compared with that in less constrained genes (28% vs. 8%). These results are explained by differences in the extent of contribution of mildly deleterious mutations to ersity and substitution.
Publisher: Cold Spring Harbor Laboratory
Date: 15-09-2023
Publisher: Elsevier BV
Date: 09-2023
Publisher: Frontiers Media SA
Date: 08-07-2021
DOI: 10.3389/FGENE.2021.661276
Abstract: Genetic improvement for quality traits, especially color and meat yield, has been limited in aquaculture because the assessment of these traits requires that the animals be slaughtered first. Genotyping technologies do, however, provide an opportunity to improve the selection efficiency for these traits. The main purpose of this study is to assess the potential for using genomic information to improve meat yield (soft tissue weight and condition index), body shape (cup and fan ratios), color (shell and mantle), and whole weight traits at harvest in the Portuguese oyster, Crassostrea angulata . The study consisted of 647 oysters: 188 oysters from 57 full-sib families from the first generation and 459 oysters from 33 full-sib families from the second generation. The number per family ranged from two to eight oysters for the first and 12–15 oysters for the second generation. After quality control, a set of 13,048 markers were analyzed to estimate the genetic parameters (heritability and genetic correlation) and predictive accuracy of the genomic selection for these traits. The multi-locus mixed model analysis indicated high estimates of heritability for meat yield traits: 0.43 for soft tissue weight and 0.77 for condition index. The estimated genomic heritabilities were 0.45 for whole weight, 0.24 for cup ratio, and 0.33 for fan ratio and ranged from 0.14 to 0.54 for color traits. The genetic correlations among whole weight, meat yield, and body shape traits were favorably positive, suggesting that the selection for whole weight would have beneficial effects on meat yield and body shape traits. Of paramount importance is the fact that the genomic prediction showed moderate to high accuracy for the traits studied (0.38–0.92). Therefore, there are good prospects to improve whole weight, meat yield, body shape, and color traits using genomic information. A multi-trait selection program using the genomic information can boost the genetic gain and minimize inbreeding in the long-term for this population.
Publisher: The Royal Society
Date: 07-2018
Abstract: A number of previous studies reported that gene expression, tissue specificity, gene essentiality and the number of protein–protein interactions influence the rate of protein evolution. Here we investigated the influence of effective population size ( N e ) on these determinants of protein evolution. For this purpose, we compared the ratio of non-synonymous-to-synonymous ersities ( π N / π S ) estimated for protein-coding genes of Mus musculus castaneus and Mus musculus musculus : populations with high and low N e respectively. Our results revealed that the difference between π N / π S estimated for genes with high and low expression levels was significantly smaller for M. m. musculus compared to that observed for M. m. castaneus . The difference between the π N / π S of broadly expressed and tissue specific genes was much higher for M. m. castaneus compared to that of M. m. musculus. Furthermore, the difference between the π N / π S computed for essential and non-essential genes was much smaller for M. m. musculus than M. m. castaneus . A similar pattern was observed for genes involved in many protein–protein interactions versus those involved in one. These results suggest that the effects of the determinants on protein evolution were much reduced for the population with small N e due to increased genetic drift.
Location: United Kingdom of Great Britain and Northern Ireland
Start Date: 05-2016
End Date: 12-2020
Amount: $570,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2018
End Date: 12-2018
Amount: $384,671.00
Funder: Australian Research Council
View Funded ActivityStart Date: 08-2016
End Date: 08-2022
Amount: $178,464.00
Funder: Australian Research Council
View Funded ActivityStart Date: 02-2018
End Date: 12-2023
Amount: $401,573.00
Funder: Australian Research Council
View Funded ActivityStart Date: 06-2015
End Date: 12-2018
Amount: $740,880.00
Funder: Australian Research Council
View Funded Activity