Sexual selection and the accumulation of deleterious mutations. Mutation is the ultimate source of all genetic variation. Understanding the nature of mutation, its frequency, the distribution of effects, and the forces of selection that remove mutational load from populations is therefore a central concern of genetics. The accumulation of mutational load in endangered species and in human populations, where the forces of selection tend not to operate, has the potential to create serious proble ....Sexual selection and the accumulation of deleterious mutations. Mutation is the ultimate source of all genetic variation. Understanding the nature of mutation, its frequency, the distribution of effects, and the forces of selection that remove mutational load from populations is therefore a central concern of genetics. The accumulation of mutational load in endangered species and in human populations, where the forces of selection tend not to operate, has the potential to create serious problems. We will determine the efficacy of sexual selection in preventing deleterious mutations from accumulating in populations. This project will provide research training opportunities in quantitative genetics, an enabling discipline in Biology.Read moreRead less
The Geometry of Genetic Limits to Evolutionary Change. Genetic limits to evolutionary change are a fundamental issue for plant and animal improvement, as well as understanding how natural populations may respond to human-induced changes such as habitat degradation and climate change. Because we still know very little about how genetic variation is distributed among the multiple traits that are likely to respond to selection in such circumstances, we have no way of directly measuring the evoluti ....The Geometry of Genetic Limits to Evolutionary Change. Genetic limits to evolutionary change are a fundamental issue for plant and animal improvement, as well as understanding how natural populations may respond to human-induced changes such as habitat degradation and climate change. Because we still know very little about how genetic variation is distributed among the multiple traits that are likely to respond to selection in such circumstances, we have no way of directly measuring the evolutionary potential of any natural population. In this proposal, we develop the theory, statistical tools, and experimental designs to investigate the nature and prevalence of these multivariate genetic constraints.Read moreRead less
Nanotechnology in nature: the evolutionary significance of iridescent ultraviolet colouration in butterflies. Nanostructural colour is a novel and interesting biological phenomenon that has potential application in textile and paint industries. This research has the potential to uncover knowledge relevant to future genetic manipulation and/or artificial synthesis of this trait for industry. Fundamental benefits will include a contribution to our understanding of evolution and biological diversit ....Nanotechnology in nature: the evolutionary significance of iridescent ultraviolet colouration in butterflies. Nanostructural colour is a novel and interesting biological phenomenon that has potential application in textile and paint industries. This research has the potential to uncover knowledge relevant to future genetic manipulation and/or artificial synthesis of this trait for industry. Fundamental benefits will include a contribution to our understanding of evolution and biological diversity, enhancement of Australia's research profile, and the cultivation of new scientific expertise. This proposal also promises to benefit the Australian scientific community through the establishment of collaborative links with universities in the USA and UK, and to increase mainstream awareness of Australia's stunning natural resources.Read moreRead less
Searching for genes influencing reading ability using multivariate genomic linkage analysis and allelic association analysis. Following from the replicated linkages of reading disability to loci on chromosomes 6 & 18, this study examines linkage of these same regions to a range of reading measures in an unselected sample of twins and siblings. Preliminary univariate linkage scans of two neuropsychological reading indices suggest linkage to loci on two chromosomes. Our next step is to include rea ....Searching for genes influencing reading ability using multivariate genomic linkage analysis and allelic association analysis. Following from the replicated linkages of reading disability to loci on chromosomes 6 & 18, this study examines linkage of these same regions to a range of reading measures in an unselected sample of twins and siblings. Preliminary univariate linkage scans of two neuropsychological reading indices suggest linkage to loci on two chromosomes. Our next step is to include reading measures of orthographic skill and phonological decoding in a multivariate linkage analysis with the other reading indices and with measures of IQ and academic achievement. Multivariate linkage increases the power of detecting quantitative traits and assists in defining the phenotype related to the locus. We then aim to identify the functional gene through allelic association analysis. Identification of QTLs for reading ability may lead to practical outcomes such as the behavioural and biomedical management of reading deficits, which may then benefit areas such as scholastic achievement.Read moreRead less
Locating genes for elementary and complex cognitive abilities using genetic linkage and association analysis. This study aims to identify genes influencing cognitive ability by using multiple measures of cognition in combination with genetic linkage and association analyses. Multiple measures can increase the statistical power of finding a gene and provide a more comprehensive framework for charting the functional role of genes. The outcome of locating genes for cognition will provide insight i ....Locating genes for elementary and complex cognitive abilities using genetic linkage and association analysis. This study aims to identify genes influencing cognitive ability by using multiple measures of cognition in combination with genetic linkage and association analyses. Multiple measures can increase the statistical power of finding a gene and provide a more comprehensive framework for charting the functional role of genes. The outcome of locating genes for cognition will provide insight into biological functions of the brain which affect human intellect, and will have downstream practical applications which could include better educational, behavioural and biomedical management of learning and memory disorders, and of other intellectual disabilities.Read moreRead less
Quantitative and Molecular Genetic Analysis of Cognition. This study attempts to unravel the pathways through which genes may exert their influence on cognitive processes by identifying some of the genes associated with normal variation in cognitive ability. Using the cognitive phenotypes we have collected, both linkage and association analysis will be used to find QTLs (locations on the chromosomes at which specific genes contribute to a quantitative trait) associated with processing speed and ....Quantitative and Molecular Genetic Analysis of Cognition. This study attempts to unravel the pathways through which genes may exert their influence on cognitive processes by identifying some of the genes associated with normal variation in cognitive ability. Using the cognitive phenotypes we have collected, both linkage and association analysis will be used to find QTLs (locations on the chromosomes at which specific genes contribute to a quantitative trait) associated with processing speed and other specific abilities. The research will enhance our understanding of the biological mechanisms influencing brain function and paves the way for the genetic dissection of the brain.Read moreRead less
Locating genes for cognitive traits using linkage and association analyses. Our study is the 1st in the world to find significant linkage for IQ.The dataset is one of only 2 such in the world (based on sample size, range & type of measures).Identifying genes for cognitive ability using healthy subjects is important in understanding individual differences in normal cognitive functioning, but it may also provide clues into the underlying mechanisms of impaired cognitive ability. Diverging conditio ....Locating genes for cognitive traits using linkage and association analyses. Our study is the 1st in the world to find significant linkage for IQ.The dataset is one of only 2 such in the world (based on sample size, range & type of measures).Identifying genes for cognitive ability using healthy subjects is important in understanding individual differences in normal cognitive functioning, but it may also provide clues into the underlying mechanisms of impaired cognitive ability. Diverging conditions like reading disorder, schizophrenia, depression, alcoholism, and dementia all share deficits in cognitive ability.Downstream practical applications of identifying 'genes for cognition' include better educational, behavioural and biomedical management of learning and memory disorders, and other intellectual disabilities.Read moreRead less
Identifying genes for cognition. We have established a large twin sample and are the Australian arm of an international consortium to identify genes for cognition. This work will transform our understanding of brain functions that affect normal cognitive functioning. It has potentially enormous public health significance by providing clues into the underlying mechanisms of impaired cognitive ability. Many different conditions affect people's ability to think and remember (e.g. schizophrenia, dem ....Identifying genes for cognition. We have established a large twin sample and are the Australian arm of an international consortium to identify genes for cognition. This work will transform our understanding of brain functions that affect normal cognitive functioning. It has potentially enormous public health significance by providing clues into the underlying mechanisms of impaired cognitive ability. Many different conditions affect people's ability to think and remember (e.g. schizophrenia, dementia). By understanding how cognitive processes work in healthy individuals, we can better identify the fundamental mechanisms of impaired cognitive ability. This may have future applications for treating brain dysfunction, and managing memory of intellectual disabilities.Read moreRead less