Identification Of Novel Genes Influencing Development Of Type 2 Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$558,920.00
Summary
Type 2 diabetes is usually associated with obesity and is often part of a wider disturbance affecting an individual's energy metabolism. The number of affected people with type 2 diabetes has trebled since 1981 in Australia and is still increasing. Apart from individual suffering, this presents a major public health burden for the country (approx $3 billion annually). Currently available lifestyle based and pharmaceutical therapies are inadequate to control the increasing numbers of affected ind ....Type 2 diabetes is usually associated with obesity and is often part of a wider disturbance affecting an individual's energy metabolism. The number of affected people with type 2 diabetes has trebled since 1981 in Australia and is still increasing. Apart from individual suffering, this presents a major public health burden for the country (approx $3 billion annually). Currently available lifestyle based and pharmaceutical therapies are inadequate to control the increasing numbers of affected individuals. Unfortunately the cause of disease is poorly understood, although genetic factors are known to be important, in other words it runs in the family. This project proposes to identify some of these factors (genes) and how they contribute to the disease. Using molecular flags on the DNA (like DNA fingerprinting) we have previously found that a small region on chromosome 12 is likely to carry one or more of these disease genes. But there are over 100 genes in the region. To help choose the most likely candidates first for testing, we have developed an automated computer database searching program ranked the genes based on what is already known about them. We have also taken a large number of physiological measures in a large group of people. Some of these measures are controlled by the same chromosome 12 region - thus to improve our chances of finding the genes quickly we will look at those that change the most between people with diabetes and people without diabetes. In this project we shall investigate the 20 genes most likely affect diabetes based on changes in physiological measures and what is already known about them. A successful finding means we will know more about the mechanism of disease development and be able to better develop new therapies for treatment and prevention. If none of these genes are the culprit, we would continue examination of the next set of genes likely to be involved and so on until we are successful.Read moreRead less
Elucidating Genetic Mechanisms Responsible For Familial Hyperaldosteronism Type II
Funder
National Health and Medical Research Council
Funding Amount
$424,812.00
Summary
Primary aldosteronism (PAL) is the commonest specifically treatable and potentially curable form of hypertension (high blood pressure), a common disease, expensive to treat, with serious morbidity and mortality. This project will use cutting edge technology to gain new knowledge concerning how genes regulate the body's production of aldosterone (salt hormone), which will help us understand how PAL develops and how common it is, and could lead to better approaches to diagnosis and treatment.
Kallikrein Gene Variants In Prostate Cancer: Analysis Of Gene Regulation And Diagnostic/Prognostic Use
Funder
National Health and Medical Research Council
Funding Amount
$486,801.00
Summary
Prostate cancer is the most common male cancer in Australia. However, early detection through screening programs has proven challenging, and about 30% of the 10,000 new cases diagnosed annually already have advanced disease. Hence, there is a fundamental need for increased basic research in prostate cancer etiology (cause) and tumour biology, and a critical requirement for methods that will assist in earlier detection of the disease and predict progression. A family of proteins called kallikrein ....Prostate cancer is the most common male cancer in Australia. However, early detection through screening programs has proven challenging, and about 30% of the 10,000 new cases diagnosed annually already have advanced disease. Hence, there is a fundamental need for increased basic research in prostate cancer etiology (cause) and tumour biology, and a critical requirement for methods that will assist in earlier detection of the disease and predict progression. A family of proteins called kallikreins (including prostate specific antigen, PSA) are often associated with clinical features of prostate cancer. We will characterise genetic variants (polymorphisms) in kallikrein genes that are consistently over-produced in prostate cancer, and determine whether they cause more protein to be produced in cells grown in the laboratory and in tumour tissue, and-or give rise to different expression products or splice variants. We will use bioinformatics (computer programs) to characterise published kallikrein gene sequences and to examine them for genetic variants that might be related to changes in gene expression or to splice variants. We will then use a case-control study, involving 1200 men with prostate cancer and 1200 healthy men, to determine whether these gene variants are associated with an increased risk of prostate cancer or with clinical aspects of the disease. Finally, we will examine the functional significance of the gene variants. This project represents an important and novel combination of molecular biology with the study of clinical disease at the population level, in the relatively new field of molecular epidemiology. It will clarify the role of kallikrein gene variants in prostate cancer risk and progression. The technologies may ultimately prove useful clinically for diagnosis of prostate cancer or for monitoring of treatment and prognosis, and hopefully will assist in clinical decision-making.Read moreRead less
GENETIC PREDICTION OF FRACTURE IN A RISK-STRATIFIED POPULATION
Funder
National Health and Medical Research Council
Funding Amount
$363,000.00
Summary
Osteoporosis is a condition characterised by excessive bone loss and impaired bone quality, which ultimately results in fracture with minimal trauma. Osteoporosis affects 27% of women and 11% of men aged 60 years or above in the community, and costs Australia around $7 billion each year. Individuals with low bone mineral density (BMD) have a significantly higher risk of fracture than those with normal BMD. In the long-term (14-year) Dubbo Osteoporosis Epidemiology Study, more than half of indivi ....Osteoporosis is a condition characterised by excessive bone loss and impaired bone quality, which ultimately results in fracture with minimal trauma. Osteoporosis affects 27% of women and 11% of men aged 60 years or above in the community, and costs Australia around $7 billion each year. Individuals with low bone mineral density (BMD) have a significantly higher risk of fracture than those with normal BMD. In the long-term (14-year) Dubbo Osteoporosis Epidemiology Study, more than half of individuals with osteoporosis (e.g., low BMD) did not sustain a fracture, while approximately 60% of fracture cases had BMD above the high risk levels. Thus, BMD alone is not a good discriminant of fracture versus non-fracture cases. It is widely known that the liability to fracture is determined in part by genes. Previous studies, including from our group, have suggested a number of candidate genes that are associated with fracture risk. The fundamental issue that this study is concerned is that how and whether genetic markers could be used to facilitate case finding. It is proposed that common variations of certain genes are associated with fracture risk independent of BMD. That is, they can identify individuals at relatively high and low fracture risk after stratification for BMD. Hence, some markers may identify those individuals likely (and unlikely) to fracture even with low (osteoporotic) BMD. Similarly, some, possibly the same, markers may identify individuals at high risk of fracture despite relatively good (ie non-osteoporotic) BMD. It is further proposed that no single gene will achieve this outcome, but rather a small set of such gene polymorphisms will provide clinically useful risk information. This effect is entirely analogous to the use of clinical risk indicators (eg, age, weight, sex, family history, etc) to assess the risk of future fracture.Read moreRead less
The Role Of The Novel Gene Herpud1 In Insulin Secretion In Type 2 Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$502,370.00
Summary
A reduced ability to secrete insulin is the cause of high blood sugar in type 2 diabetes. This study has identified a gene called Herpud1 that affects insulin secretion. By studying the effects of this gene we are improving our knowledge of the defects that occur in Type 2 diabetes. This has the potential of providing better therapeutic strategies and identifying targets for the developments of better drug development.
Identification And Characterisation Of A Gene Causing Insulin Hypersecretion In A Mouse Model Of Diabetes Susceptibility
Funder
National Health and Medical Research Council
Funding Amount
$430,320.00
Summary
Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secret ....Diabetes is a disorder primarily characterised by the inability to produce and secrete the pancreatic hormone insulin, which regulates plasma sugar levels. This results in increased sugar levels which cause diabetic complications such as retinopathy and nephropathy. The inability to produce and secrete insulin is due to both defects in function as well as a reduction in pancreatic beta cells. Paradoxically it has been shown that some patients who are at risk of develping diabetes actually secrete more insulin than normal. Furthermore it has been suggested that this increase in insulin secretion actually may be associated with the decreased production and secretion of insulin characteristic of diabetes. The DBA-2 mouse is a model of reduced insulin production and secretion when exposed to high sugar levels or diabetes. However we have shown that in the normal non-stressed state DBA-2 mice actually secrete more insulin than normal and that this occurs from a very early age, suggesting that this trait is inherited. We have subsequently performed genetic studies and have identified a segment of DNA containing 10 genes associated with increased insulin secretion in DBA-2 mice. The level of one of these genes we have called Hip1 is increased 5-fold in DBA-2 mice, providing a candidate gene for increased insulin secretion in this model of diabetes susceptibility. However, whether Hip1 is also responsible for reduced insulin production and secretion in the DBA-2 mouse is not known. Therefore the overall hypothesis of this project is that the gene Hip1 which is associated with increased insulin secretion is also responsible for reduced insulin production and secretion when DBA-2 mice are exposed to high sugar or obesity. Determining why Hip1 is increased and whether it results in diabetes in DBA-2 mice may provide a reasonable candidate for the development of therapeutic interventions which may prevent the progression of diabetes in some patients.Read moreRead less
How Does Disruption Of Circadian Rhythms Induce Diabetes?
Funder
National Health and Medical Research Council
Funding Amount
$631,782.00
Summary
Increasing evidence suggests that disturbed circadian rhythms initiate and amplify metabolic and cardiovascular disease. The increasing and already high proportion of workers engaged in shiftwork, and increased frequency of disruption of these rhythms in the population more generally, implicate this body system as contributing to the growing epidemic of obesity and diabetes and related disorders in our community and world-wide. While we are now beginning to understand how our rhythms are synchro ....Increasing evidence suggests that disturbed circadian rhythms initiate and amplify metabolic and cardiovascular disease. The increasing and already high proportion of workers engaged in shiftwork, and increased frequency of disruption of these rhythms in the population more generally, implicate this body system as contributing to the growing epidemic of obesity and diabetes and related disorders in our community and world-wide. While we are now beginning to understand how our rhythms are synchronised to night and day, how this rhythmicity is linked to our organs in the normal and common disease states such as diabetes is poorly understood. The discovery of a special set of genes, called clock genes that function in all of the cells in our bodies and strongly influence the function of our organs such as the liver, pancreas and heart has been particularly important. We hypothesise that both environmentally (exogenous) and genetically (endogenous) induced disruption of circadian rhythms causes metabolic dysfunction. This is due to altered central and peripheral clock gene expression rhythms, which in turn alter metabolic rhythms and impair glucose homeostasis. This project aims to determine the impact of disrupted rhythmicity on metabolism with a particular emphasis on the possibility that the disrupted rhythmicity may be a predisposing factor for the development of diabetes.Read moreRead less