Identification Of Genes For X-linked Mental Retardation.
Funder
National Health and Medical Research Council
Funding Amount
$675,228.00
Summary
We propose to identify novel heritable causes of intellectual disability using 22 large and well-characterised families from Australia. In these families we have refined the location of the genetic defect to the chromosome X and excluded the contribution of all so far known genes. We will achieve this using the technology of massive parallel sequencing. At the completion of the project we will have identified novel causes of intellectual disability and devised tests to identify them.
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.
Gene Variants Related To Bone Density And Fracture.
Funder
National Health and Medical Research Council
Funding Amount
$330,375.00
Summary
Bone density and osteoporosis have a genetic component. Identifying genes that are involved in determining bone density may permit advances in controlling osteoporosis. We have identified a variant that is related to bone density high enough to protect individuals four fold against Colle's fracture, the common wrist fracture seen in women. In addition, some people with bone fracture at the hip, or low bone density, have mutations in this gene. The gene is a master regulator of the cells that mak ....Bone density and osteoporosis have a genetic component. Identifying genes that are involved in determining bone density may permit advances in controlling osteoporosis. We have identified a variant that is related to bone density high enough to protect individuals four fold against Colle's fracture, the common wrist fracture seen in women. In addition, some people with bone fracture at the hip, or low bone density, have mutations in this gene. The gene is a master regulator of the cells that make bone: this gives hope that it may be possible to alter bone formation through this master regulator.Read moreRead less
Mapping Of Genetic Traits In Experimental Models Using Databases
Funder
National Health and Medical Research Council
Funding Amount
$237,750.00
Summary
The project aims to detect genes that influence human traits. These traits could be a disease such as diabetes or they may be much less sinister, representing hearing range as an example. Many of these traits are difficult to detect because they are governed by many genes which may also interact with the environment to influence the trait. In order to detect genes in these traits we would like to simplify the complex interactions by eliminating the environment as a potential cause or concentrati ....The project aims to detect genes that influence human traits. These traits could be a disease such as diabetes or they may be much less sinister, representing hearing range as an example. Many of these traits are difficult to detect because they are governed by many genes which may also interact with the environment to influence the trait. In order to detect genes in these traits we would like to simplify the complex interactions by eliminating the environment as a potential cause or concentrating on a particular population where the incidence appears to be much greater. In human populations we have no control over the environmental exposures and we cannot restrict their movements. For this reason many genetic studies have been conducted in mice. Many strains of mice have been generated. Their environment can be strictly controlled, enabling a much better identification of disease genes. Since mice and humans share much of their genome they also share many of their genes and are often afflicted by the same diseases. Thus if we identify genes in mice we have a very good chance of identifying the equivalent human genes. The completion of sequencing for the human genome is being closely followed by the completion of the mouse genome, precisely because mice have been used for over 100 years for genetic studies. The data generated from these sequencing efforts and prior genetic studies is now accumulating in vast databases. These databases of DNA information can be used to map genes for traits. The idea is to determine the trait measurement for many mice in different strains and compare these trait levels to the DNA state (genotype) of markers in the genome of the strains. If these are associated it indicates that the marker is situated close to a gene influencing the trait. This narrows the search considerably. Without this strategy we would have the daunting task of identifiying trait genes from many thousands of potential candidates.Read moreRead less
The Role Of Intersectin-1 In Endocytic Anomalies: Implications For Down Syndrome And Alzheimer's Disease
Funder
National Health and Medical Research Council
Funding Amount
$510,500.00
Summary
Individuals with Down syndrome have three copies of human chromosome 21, rather than the normal two. We have discovered a gene called Intersectin-1, located on human chromosome 21, that is expressed at higher levels than normal in individuals with Down syndrome. Intersectin-1 has a role in endocytosis, a process whereby cells take up molecules from the outside. Endocytosis occurs in all cells but is highly specialised in the brain where chemical transmitters are released and then rapidly recover ....Individuals with Down syndrome have three copies of human chromosome 21, rather than the normal two. We have discovered a gene called Intersectin-1, located on human chromosome 21, that is expressed at higher levels than normal in individuals with Down syndrome. Intersectin-1 has a role in endocytosis, a process whereby cells take up molecules from the outside. Endocytosis occurs in all cells but is highly specialised in the brain where chemical transmitters are released and then rapidly recovered by endocytosis in a process enabling neurones to pass signals to one another. A disturbance in endocytosis has been reported as the earliest hallmark of Alzheimer's disease in both non-Down syndrome and Down syndrome individuals. This disturbance is characterised by the presence of enlarged endosomes (small packages in neuronal cells containing chemical neurotransmitters formed during endocytosis). These enlarged endosomes are present long before the characteristic plaques of Alzheimer's disease appear. Since all individuals with Down syndrome develop Alzheimer's-like neuropathology, there must be a common disease mechanism that can be traced to the extra gene dosage from chromosome 21. We propose that a malfunctioning of Intersectin-1 is this common mechanism and we aim to test our hypothesis by the generation and analysis of mouse models of disrupted endocytosis.Read moreRead less
Crohn's disease is a severe, chronic inflammatory disease of the gut which affects up to 50,000 Australians. The majority of patients develop the disease in their twenties, with significant impact on their quality of life. Our preliminary work has identified a novel gene, which could potentially cause a critical reduction in the production of anti-bacterial proteins by cells in the small bowel. Exploring the function of this gene in relation to clinical outcome could lead to better treatment.
The Identification Of Novel Genes Involved In The Initiation And Development Of Thyroid Neoplasia
Funder
National Health and Medical Research Council
Funding Amount
$227,545.00
Summary
Thyroid cancer is the most frequently diagnosed endocrine malignancy, comprising 1% of all human malignancy. However, its actual occurrence indicated by autopsy studies may be as high as 10%. To date, a number of genes, both oncogenes (genes that are inappropriately switched on and take part in the process of tumour development) and tumour suppressor genes (genes that are switched off and lose their protective role against tumour development), have been implicated in the development of thyroid c ....Thyroid cancer is the most frequently diagnosed endocrine malignancy, comprising 1% of all human malignancy. However, its actual occurrence indicated by autopsy studies may be as high as 10%. To date, a number of genes, both oncogenes (genes that are inappropriately switched on and take part in the process of tumour development) and tumour suppressor genes (genes that are switched off and lose their protective role against tumour development), have been implicated in the development of thyroid cancer. However mutations, mistakes in the genetic code, of these genes account for only a small percentage of thyroid tumours and none of these genes have been shown to be useful as clear prognostic markers for tumour progression or aggressiveness. The merging of the 2 fields of cytogenetics (the study of chromosomes) and molecular genetics (the study of genes at the DNA and RNA level) has strengthened our ability to understand the process of tumour development. We are proposing use of a technique called Comparative Genomic Hybridisation to aid in the identification of new genes associated with tumour development in both benign and malignant thyroid disease. This technique has already been used to aid in the location of genes with a role in ovarian and brain cancer and in some familial syndromes characterised by breast and gastrointestinal malignancies. This method involves the detection of regions of chromosomal amplifications or deletions in tumour DNA that is fluorescently labelled (green), mixed with normal human DNA also fluorescently labelled (red). If the tumour contains regions of amplification (likely housing an oncogene), analyses show increased green fluorescence and if deletions are present (likely housing a tumour suppressor gene), analyses show increased red fluorescence. Chromosomal regions identified by this method will be further analysed to identify the precise genes they contain and establish a role for these genes in the development of thyroid tumours.Read moreRead less
Identification And Characterisation Of Nessy; A Novel Gene Important For T Cell Differentiation.
Funder
National Health and Medical Research Council
Funding Amount
$250,500.00
Summary
This project aims to identify, and understand the function of, a new gene involved in the immune system. The Nessy mouse strain was developed in Prof. Goodnow s Medical Genome Centre at the Australian National University. It has a mutation in an unknown gene which causes a defect in T lymphocytes- white blood cells which are important for fighting infection. This project has three major aims: 1) to identify the gene. 2) to understand the defects in T lymphocytes caused by the gene. 3) to identif ....This project aims to identify, and understand the function of, a new gene involved in the immune system. The Nessy mouse strain was developed in Prof. Goodnow s Medical Genome Centre at the Australian National University. It has a mutation in an unknown gene which causes a defect in T lymphocytes- white blood cells which are important for fighting infection. This project has three major aims: 1) to identify the gene. 2) to understand the defects in T lymphocytes caused by the gene. 3) to identify which other genes interact with the mutant gene. Thus will allow us to understand how the mutant gene causes the T lymphocyte defects. This project will improve our understanding of the development and functioning of T lymphocytes, which play a central role in the immune system. Since the genomes of mice and humans are very similar, it is likely that we will be able to identify a human counterpart to the Nessy gene.Read moreRead less
Controlling HIV-1 Replication In Macrophages: Cellular Regulation Of Tat Expression
Funder
National Health and Medical Research Council
Funding Amount
$466,500.00
Summary
Monocytes in the blood and macrophages in the tissues are the scavenger cells of the body's immune system. They are among the first cells to become infected with HIV and harbour the virus for the lifetime of the cell, which can be up to several years. While monocytes are only infected at low frequency, macrophages in tissues can be infected in high numbers and can contribute significantly to virus production. Current potent combination therapies are unable to clear the virus from these cells and ....Monocytes in the blood and macrophages in the tissues are the scavenger cells of the body's immune system. They are among the first cells to become infected with HIV and harbour the virus for the lifetime of the cell, which can be up to several years. While monocytes are only infected at low frequency, macrophages in tissues can be infected in high numbers and can contribute significantly to virus production. Current potent combination therapies are unable to clear the virus from these cells and have limited efficacy in this cell type. There are no treatments which specifically target HIV infection in these important viral reservoirs. We have found that in a laboratory model of HIV infection in macrophages, the infection changes from active and productive to chronic and non-productive over the course of several weeks. This change is characterised by a decrease in one of the virus' important regulatory proteins, Tat. In this project, we aim to determine how the cells induce this change in the virus' growth. This may lead to novel ways in which HIV could be controlled in these important cells by targeting cellular rather than viral proteins. Controlling infection in macrophages and preventing spread of the virus to other cells would assist with the problem of the virus rebounding rapidly when patients stop or interrupt therapy and would help with long term treatment and management, leading to eventual eradication of the virus from the body.Read moreRead less