Identification Of Genes Important In Myeloid And Haemopoietic Development By Genetic Screening In Zebrafish
Funder
National Health and Medical Research Council
Funding Amount
$425,250.00
Summary
Zebrafish have emerged as a powerful experimental model in developmental genetics. Their favourable attributes include their reproductive biology, the optical clarity of embryos, and the accessibility of embryos for experimental procedures. Previous studies overseas have recovered over 1500 strains of zebrafish with inherited diseases due to induced mutations in about 500 genes. Many of these zebrafish have abnormalities of unexpected precision and are leading to new genes with novel specialized ....Zebrafish have emerged as a powerful experimental model in developmental genetics. Their favourable attributes include their reproductive biology, the optical clarity of embryos, and the accessibility of embryos for experimental procedures. Previous studies overseas have recovered over 1500 strains of zebrafish with inherited diseases due to induced mutations in about 500 genes. Many of these zebrafish have abnormalities of unexpected precision and are leading to new genes with novel specialized functions. About 50 mutant zebrafish strains exist in which red blood cell development is perturbed - this was easily recognized because the transparency of embryos enabled lack of blood be easily seen. Our new studies aim primarily to recover mutant zebrafish with disorders of white blood cell formation. We have identified methods to recognize failure of white blood cell formation in zebrafish, and will employ these methods to look for inherited disorders that specifically affect white blood cell development in a process called genetic screening. Fish with different sets of randomly mutated genes will be systematically screened to identify those with abnormal white blood cell development. We have tested our approach and identified several mutants affecting white blood cell development. Once these new strains of fish are identified, we will find the genetic lesion responsible for the abnormality in several of the most interesting strains by gene mapping and positional cloning. Hence, the mutant zebrafish identified in the screen will eventually lead to the discovery of new genes important in white blood cell growth and development. The fish themselves will provide insights into the causes of congenital diseases of white blood cells. Since many genes involved in early development are also important in cancer, we believe that newly identified genes will also help understand the causes of abnormal growth of white blood cells in leukaemia.Read moreRead less
The Role Of GRHL-3, A Mammalian Homologue Of Drosophila Grainyhead, In Neural Tube Development
Funder
National Health and Medical Research Council
Funding Amount
$496,500.00
Summary
Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first ....Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first few hours of life. These abnormalities occur frequently (1-1000 live births) and are a direct result of failure of the neural tube to close during embryogenesis. NTDs are influenced by both environmental and genetic factors. The best characterised environmental factor is the dietary supplement folate, which when administered before conception results in a reduction in the incidence of spina bifida. The genetic complexity is evidenced by the array of mouse genetic mutations that give rise to NTDs. One of these mouse mutations, known as Curly tail (ct), has served as the major animal model of human NTDs. This is because the ct mice are resistant to folate administration (like most of the cases of spina bifida currently seen in patients) and because the mice seem to have normal development in virtually all other organ systems. Ironically, the genetic mutation that causes the curly tail phenotype has remained undiscovered for over 50 years. We have now identified the gene mutated in the curly tail mice. This gene is highly conserved in humans suggesting that it will play a similar role in neural tube development in man. The gene, known as GRHL-3, is a descendant of a fly gene critical for development of the nervous system in that organism. The studies we propose here will examine the developmental pathways involved in normal neural tube closure in mice and humans and will impact on our understanding of these devastating congenital malformations.Read moreRead less
Analysis Of The Function Of The Presenilin Genes During Embryogenesis.
Funder
National Health and Medical Research Council
Funding Amount
$197,317.00
Summary
The presenilin genes are essential for normal human mental health. Deleterious changes in presenilin genes are the root cause of 60% of Alzheimers Disease that is inherited within families (ie. Oearly onsetO Alzheimers disease) and of 10% of all Alzheimers disease. Normal presenilin genes are also necessary for correct embryo development. There is evidence that the proteins produced by the presenilin genes interact with other proteins such as those produced by the Notch genes. Changes in Notch g ....The presenilin genes are essential for normal human mental health. Deleterious changes in presenilin genes are the root cause of 60% of Alzheimers Disease that is inherited within families (ie. Oearly onsetO Alzheimers disease) and of 10% of all Alzheimers disease. Normal presenilin genes are also necessary for correct embryo development. There is evidence that the proteins produced by the presenilin genes interact with other proteins such as those produced by the Notch genes. Changes in Notch genes can also produce dementia and developmental defects. However, despite their obvious importance, we know little about how presenilin and Notch genes function and interact! We want to understand how presenilin genes interact with Notch genes and any other genes that are important for normal embryo development. To investigate this we are using the eggs of a small, freshwater fish, the zebrafish. These eggs are easily available (hundreds are produced by a female zebrafish every week), accessible and, being transparent, every cell in a developing zebrafish egg can be observed! They also develop about one hundred times faster that a human! In our experiments we will produce antibodies to the protein products of the presenilin and Notch genes of zebrafish and then use these to observe interactions between the presenilin and Notch proteins. We will observe how changes in the levels of presenilin protein in an embryo affect the function of the Notch genes and we will attempt to discover other genes that are affected by such changes. This work will be important for understanding how genes interact to create our bodies during embryo development. Also, since genes typically interact in similar ways during embryo development and in adults, the discoveries that we make will help us to understand what goes wrong when changes in the presenilin genes cause Alzheimers disease.Read moreRead less
The Molecular And Biological Roles Of Growth Inhibiting Chromatin Binding Proteins
Funder
National Health and Medical Research Council
Funding Amount
$814,843.00
Summary
Our previous work has led to the identification of mutations underlying human birth defects. Similarly, our proposed work will identify a new gene as potentially mutated in human heart defects. We will determine its overlapping functions with a related gene and elucidate their roles in embryonic development and cancer.
The Role Of Med12, A Subunit Of RNA Polymerase II Mediator, In Haemopoiesis
Funder
National Health and Medical Research Council
Funding Amount
$495,490.00
Summary
In a screen of zebrafish for mutations in blood cell development, we isolated a mutant called syrah. The mutation causing the blood defect was identified in a gene called med12, which encodes a component of the RNA transcription machinery in cells. To understand how this mutation causes a reduction in blood cells, we will identify the proteins that interact with the med12 protein. Understanding the pathway involved may lead to the discovery of new causes of human congenital blood diseases.
Contrary to traditional belief few cases of cerebral palsy are due to problems at birth. Most have earlier origins. Sophisticated new methods have found that many developmental brain disorders e.g. autism, intellectual disability and epilepsy are associated with submicroscopic but genetically large alterations in the genetic code of these children. This novel study will seek these alterations in a large group of Australian cerebral palsy families. The pilot data show novel and exciting findings.
Molecular Genetics Of The Host Response Defect In Cystic Fibrosis
Funder
National Health and Medical Research Council
Funding Amount
$564,690.00
Summary
Cystic fibrosis is the most common lethal genetic disease in Caucasian populations. Affected individuals suffer from a number of symptoms but the most serious is a chronic infect with the bacterial pathogen Pseudomonas aeruginosa. The sustained lung inflammation caused by infection with Pseudomonas aeruginosa ultimately destroys the structure of the lung to the point where it can no longer function. Gene therapy has been suggested as a possible treatment for the disease but another approach is t ....Cystic fibrosis is the most common lethal genetic disease in Caucasian populations. Affected individuals suffer from a number of symptoms but the most serious is a chronic infect with the bacterial pathogen Pseudomonas aeruginosa. The sustained lung inflammation caused by infection with Pseudomonas aeruginosa ultimately destroys the structure of the lung to the point where it can no longer function. Gene therapy has been suggested as a possible treatment for the disease but another approach is to identify the CF specific aspects of the inflammatory response and target those for therapeutic development. In our previous work we have identified several strong candidates for the inflammatory molecules in the CF lung and in this application we will test those candidates to see whether they play a major role in CF lung disease.Read moreRead less
Patched Gene Family Control Of Epidermal Development And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$521,961.00
Summary
The skin is the largest organ in the body and functions as a barrier against infection and dehydration. From a clinical perspective we need to know how to regenerate skin for better wound healing and the treatment of burns. We have identified a genetic pathway that regulates the stem cells of the skin and this research will show us the mechanism whereby the skin develops and regenerates, as well as the possible manipulations we can use to increase healing in the clinic.
Dissecting Genetic Variation For Human Complex Diseases And Traits
Funder
National Health and Medical Research Council
Funding Amount
$135,821.00
Summary
Understanding the pattern of inheritance for human common diseases such as cancers, obesity, diabetes and mental illness, is of key importance for disease diagnosis, treatment and prevention. In this project, we will develop statistical methods and software tools to analyse DNA and clinical data to better understand the genetic basis of human common diseases and to predict a person�s risk of developing disease.
Validation And Replication Of Genes Associated With Common Human Disease Using Australian Twin Families
Funder
National Health and Medical Research Council
Funding Amount
$921,224.00
Summary
The European Network for Genetic and Genomic Epidemiology (ENGAGE) aims to translate the wealth of data emerging from large-scale research efforts in molecular epidemiology into information of direct relevance to future advances in clinical medicine. ENGAGE will do this through the integration of very large datasets already available from a substantial number of large and well-characterised samples. The resulting ENGAGE resource will represent a research investment >€100M (>AU$160M) and pr ....The European Network for Genetic and Genomic Epidemiology (ENGAGE) aims to translate the wealth of data emerging from large-scale research efforts in molecular epidemiology into information of direct relevance to future advances in clinical medicine. ENGAGE will do this through the integration of very large datasets already available from a substantial number of large and well-characterised samples. The resulting ENGAGE resource will represent a research investment >€100M (>AU$160M) and provide unprecedented power to discover disease and trait susceptibility genes. QIMR will contribute 12,000 twins for ENGAGE joint analyses and provide analytical expertise in the analysis of disease and genetic data related to lifestyle and metabolic traits, with particular emphasis on cardiovascular disease, type 2 diabetes and migraine risk factors. Our laboratory will also perform vital further genetic studies to establish the causal relationship between the genetic variants concerned and the traits of interest. Most importantly, our direct participation will allow the translation of these findings into the Australian population and clinical arena.Read moreRead less