Spring 2015
Seminars are held on Thursdays in Cullimore Hall. For questions about the seminar schedule, please contact Antai Wang.
Date: April 16, 2015
Speaker: Yongzhao Shao
Departments of Population Health and Environmental Medicine,
New York University School of Medicine
Title: "Energy Stored in Deformation Fields: Opportunities for Directed Assembly in Soft Matter"
Abstract:
Common and complex diseases are often genetically heterogeneous in etiologies. Some well-known complex diseases with genetic heterogeneity include asthma, breast cancer, and diabetes. As a consequence of genetic heterogeneity, the population of individuals with disease may be decomposed into various latent sub-populations, each with disease caused by mutations at different loci (or their combinations). Most of the existing association tests for population-based case-control studies, e.g. genome-wide association studies (GWAS) fail to account for genetic heterogeneity. This paper develops a likelihood ratio test (LRT) for genome-wide association studies under genetic heterogeneity based on a binomial mixture model. In particular, a closed-form formula for the likelihood ratio test statistic is derived and an explicit asymptotic null distribution is also obtained which avoids the need of permutations for p-values. Thus, the proposed LRT is easy to implement for genome-wide association studies (GWAS). Numerical studies demonstrate that the LRT have power advantages over the commonly used Armitage trend test and other existing association tests under genetic heterogeneity. A breast cancer GWAS data set is used to illustrate the newly proposed LRT.
This talk is based on a paper published in Annals of Human Genetics (2013) by Dr. Meng Qian and the speaker.