High scorers on the personality trait neuroticism are at greatly increased risk of major depression and other neurotic disorders. Neuroticism is a personality trait that shows considerable stability over adulthood. It has a strong genetic basis and it seems that the same genes also determine risk of depression, anxiety and other neuroses. By selecting twins and sibs extremely discordant and concordant (EDAC) for neuroticism we can greatly reduce the cost and increase the power to find genes infl ....High scorers on the personality trait neuroticism are at greatly increased risk of major depression and other neurotic disorders. Neuroticism is a personality trait that shows considerable stability over adulthood. It has a strong genetic basis and it seems that the same genes also determine risk of depression, anxiety and other neuroses. By selecting twins and sibs extremely discordant and concordant (EDAC) for neuroticism we can greatly reduce the cost and increase the power to find genes influencing depression. Questionnaire responses and interviews from 15,027 Australian twins and 11,389 of their family members were reviewed to identify individuals with neuroticism scores in the top and bottom 10%. These individuals were invited to participate in a structured psychiatric interview by telephone, and to give a blood sample. Participation and DNA sampling rates were high and there was minimal evident participation bias. DNA was collected from 2,926 individuals from 884 families including 1,333 EDAC sibling pairs and over 795 parents. A preliminary genome scan on one third of this sample yields several linkage peaks suggesting genes of major effect that appear to replicate findings in similar studies conducted in Holland and England. Given these results it is highly desirable that we obtain a genome scan on the remainder of selected extreme sample. Another one third of this sample is currently being genotyped in America and here we request funds to genotype the remaining third. .If we are successful in identifying genes underlying neuroticism, we will also be able to analyse their contribution to depression and anxiety. This could lead to better drug treatments.Read moreRead less