Genetic And Phenotype Studies Of Partial Epilepsy In Gypsies
Funder
National Health and Medical Research Council
Funding Amount
$646,136.00
Summary
Epilepsy is one of the most common serious neurological disorders, which affects more than 50 million people worldwide. Genetic research, with a major contribution from Australian researchers, has led to the discovery of many rare forms of the disease caused by mutations in single genes of large effect. However, the vast majority of cases worldwide belong to the so-called genetically complex forms, involving multiple interacting genes and environmental factors. The genetically complex epilepsies ....Epilepsy is one of the most common serious neurological disorders, which affects more than 50 million people worldwide. Genetic research, with a major contribution from Australian researchers, has led to the discovery of many rare forms of the disease caused by mutations in single genes of large effect. However, the vast majority of cases worldwide belong to the so-called genetically complex forms, involving multiple interacting genes and environmental factors. The genetically complex epilepsies have proved particularly difficult to understand and the numerous genetic studies conducted so far have failed to produce important and replicable results. It is becoming increasingly clear that enormous genetic heterogeneity, with many rare mutations occurring in different affected subjects, will be a major obstacle to understanding the molecular basis of complex epilepsies. In this context, genetically isolated populations, which stem from a small number of ancestors, can be particularly helpful and revealing, since their limited genetic diversity means that the number of genes involved in causing complex epilepsies may be smaller and shared between individuals and families. In this study, we will analyze affected families, as well as non-familial cases of epilepsy, from a genetically isolated population - the European Roma-Gypsies. We will determine the number of potential susceptibility genes involved in familial forms, the overlap and differences between families, as well as the contribution of the genes identified in families to the development of sporadic epilepsy.Read moreRead less
Use Of Expression Profiling To Identify Genes Influencing Cardiovascular Risk In The Norfolk Island Population Isolate
Funder
National Health and Medical Research Council
Funding Amount
$697,409.00
Summary
This study will use a unique population isolate from Norfolk Island. We aim to identify genes that play a role in cardiovascular disease risk. Norfolk has a population of ~1200 permanent residents, most of whom are direct descendents of 18th century English Bounty mutineers and Polynesian women. We will undertake gene expression mapping to identify genomic loci that influence cardiovascular disease using samples from this population isolate.
Characterisation Of A New Localisation For Susceptibility To Inflammatory Bowel Disease On Chromosome 12
Funder
National Health and Medical Research Council
Funding Amount
$76,125.00
Summary
One of the greatest challenges facing contemporary gastroenterology is to understand the causes of the inflammatory bowel diseases in order to develop more effective therapies. Although there have been advances in treatment over the last few years, the causes of IBD are still not known. The existence of a genetic predisposition to IBD is now well established, and there is strong evidence that the disease is the result of the interaction of a number of different genes. To date, two genetic locali ....One of the greatest challenges facing contemporary gastroenterology is to understand the causes of the inflammatory bowel diseases in order to develop more effective therapies. Although there have been advances in treatment over the last few years, the causes of IBD are still not known. The existence of a genetic predisposition to IBD is now well established, and there is strong evidence that the disease is the result of the interaction of a number of different genes. To date, two genetic localisations (one on chromosome 16 and a second on chromosome 12) have been confirmed in multicentre studies. We have identified a novel localisation for disease susceptibility on chromosome 12 in the Australian population during the course of a genome scan on 73 multiplex inflammatory bowel disease families. (The importance of this localisation has been confirmed in English and American families.) This localisation is quite separate from that originally described and many genes separate the two localisations. We will refine the new localisation by fine scale mapping in the region of the localisation that we originally identified in pure Crohn's disease families. At this stage, the localisation appears not to be important in families suffering from ulcerative colitis or in families in which both CD and UC occurs (known as mixed families), though this finding will be tested. Using state of the art molecular genetics, we will then identify and characterise the gene involved. The significance of this project lies in the importance of this localisation to the understanding of underlying biochemistry and genetics of a complex disease in which multiple genes are segregating and interacting in, some as yet undefined manner.Read moreRead less
Use Of The Norfolk Island Genetic Isolate For Disease Gene Mapping
Funder
National Health and Medical Research Council
Funding Amount
$978,500.00
Summary
This gene mapping study will use a unique founder effect population to investigate two major public health disorders. We aim to identify genes that play a role in migraine and in cardiovascular disease, using a population from Norfolk Island. The Norfolk Island community is a population of ~1200 permanent residents, the majority of whom are direct descendents of 18th century English Bounty mutineers and Polynesian women. We will undertake a full genome scan to identify migraine gene loci and QTL ....This gene mapping study will use a unique founder effect population to investigate two major public health disorders. We aim to identify genes that play a role in migraine and in cardiovascular disease, using a population from Norfolk Island. The Norfolk Island community is a population of ~1200 permanent residents, the majority of whom are direct descendents of 18th century English Bounty mutineers and Polynesian women. We will undertake a full genome scan to identify migraine gene loci and QTL that influence cardiovascular disease using samples from this population isolate.Read moreRead less
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
Investigation Of The Genetic Basis Of Insulin Hypersecretion In A Mouse Model Of Pancreatic Islet Failure
Funder
National Health and Medical Research Council
Funding Amount
$406,980.00
Summary
Type 2 diabetes is a chronic disease that is associated with blindness, kidney failure, heart attacks and stroke and these are secondary to high blood sugar levels. Thus, determining the cause of high blood sugar levels in type 2 diabetes will lead to better management of the disease and ease the financial burden on the public health system. High blood sugar in type 2 diabetes results from the inability of the body to secrete enough insulin. Insulin is the main hormone that lowers blood sugar le ....Type 2 diabetes is a chronic disease that is associated with blindness, kidney failure, heart attacks and stroke and these are secondary to high blood sugar levels. Thus, determining the cause of high blood sugar levels in type 2 diabetes will lead to better management of the disease and ease the financial burden on the public health system. High blood sugar in type 2 diabetes results from the inability of the body to secrete enough insulin. Insulin is the main hormone that lowers blood sugar levels and is produced by the pancreas. The reason for reduced insulin secretion in type 2 diabetes is not known. Paradoxically, it has been shown that some people who are at an increased risk of developing diabetes (eg people with obesity or a family history of diabetes) secrete more insulin than normal. It is not clear why this is, but a few studies have suggested that reducing insulin secretion in these circumstances can protect the pancreas and preserve its ability to secrete the appropriate amount of insulin. The DBA-2 is a mouse strain that like humans with type 2 diabetes, its pancreas can also fail to secrete the appropriate amount of insulin and under these circumstances becomes diabetic. Furthermore our laboratory has generated evidence that shows that like people who are at risk of diabetes, DBA-2 mice in fact secrete more insulin prior to becoming diabetic. Whether the cause of this increased insulin secretion is linked to the eventual reduction of secretion is not known. The aim of this study is to identify the gene that causes increased insulin secretion in the DBA-2 mouse. Furthermore, genetically manipulated animals will be produced that contain only this gene to determine its effect on insulin secretion. Should the identification of this gene be related to the eventual failure of the pancreas to secrete enough insulin, then it would provide a target for drug therapy to correct insulin levels and therefore reduce blood sugar levels.Read moreRead less