Screening and characterisation of novel platelet candidate genes derived from genome-wide association studies for function in relation to haemostasis and thrombosis in the model organism Danio rerio. (360G-Wellcome-082597_Z_07_Z)

Platelets play a central role in atherothrombosis (AT) and death from myocardial infarction (MI). Our research aims to determine to which extent platelet-gene sequence variation contributes to the risk of AT. Parallel strategies of genome-wide association studies in MI patients and in-depth studies of platelets with an aberrant functional phenotype by transcriptome- and proteome-based analysis, have identified candidate genes in platelets conferring risk for AT. This application addresses the ne ed for a high-throughput method of studying the function of those genes with a hitherto unknown role in platelets. Based on successful feasibility studies the zebrafish has been chosen, which has the unique advantages of being both genetically tractable and a relevant model organism for studying vertebrate haemostasis. Protein translation from ~100 genes will be blocked using antisense oligonucleotides, and phenotypes of spontaneous bleeding or altered kinetics of laser-induced thrombus format ion recorded. Detection of subtle gain- and loss-of-function phenotypes will be enhanced using genetically-modified zebrafish predisposed towards bleeding or thrombosis. The most promising genes will be characterised in even greater detail using null mutants created by target-selected mutagenesis (TILLING). Together with functional studies on humans, these studies will contribute to an increase in knowledge of the mechanism of AT.