University of Michigan, Center for Statistical Genetics
Presents
CSG Seminar Speaker: Andrew Morris
Wellcome Trust Centre for Human Genetics, Oxford University
Speaking On: Discovery and fine-mapping of type 2 diabetes (T2D) susceptibility loci via trans-ethnic meta-analysis.
The majority of genome-wide association studies (GWAS) of T2D susceptibility have been undertaken in populations of European ancestry, which contain only a subset of human genetic variation, and thus are insufficient to fully characterise risk variants in other ethnic groups. More recent T2D GWAS have been performed, with great success, in populations from other ancestry groups. These studies have provided initial evidence of overlap in T2D susceptibility loci across ancestry groups and coincident risk alleles at lead SNPs between diverse populations. Consequently, we would expect to improve power to detect novel susceptibility loci for the disease and enhance fine-mapping resolution of causal variants by combining GWAS across ancestry groups through trans-ethnic meta-analysis because of increased sample size and differences in the structure of linkage disequilibrium (LD) between such diverse populations. In this seminar, I will present the results of a large-scale trans-ethnic meta-analysis of T2D GWAS from populations of European, East Asian, South Asian, and Mexican and Mexican American ancestry, in a total of 26,488 cases and 83,964 controls, and discuss the novel insights they have provided into the underlying genetic architecture of the disease. I will also present methodology for trans-ethnic fine-mapping that takes account of differences in patterns of LD between diverse populations, and demonstrate the utility of this approach in localising causal variants at five established T2D susceptibility loci by combining GWAS in 21,997 cases and 42,730 controls from populations of European, East Asian, South Asian, Hispanic and African American ancestry.
Monday, November 11, 2013
1:00 P.M.
1755, SPH I
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University of Michigan, Center for Statistical Genetics
Presents
CSG Seminar Speaker
Simon Gravel
McGill University
Speaking On:
Reconstructing Native American Migrations from Whole-genome and Whole-exome Data
There is great scientific and popular interest in understanding the genetic history of populations in the Americas. We wish to understand when different regions of the continent were inhabited, where settlers came from, and how current inhabitants relate genetically to earlier populations. The 1000 Genomes Project provides a unique opportunity for improving our understanding of population genetic history by providing over a hundred sequenced low coverage genomes and exomes from Colombian (CLM), Mexican-American (MXL), and Puerto Rican (PUR) populations. I will present new methods for modeling these admixed genomes and reconstruct of pre- and post-Columbian migration histories.
These analyses suggest that Native American ancestry in PUR is most closely related to populations surrounding the Orinoco River basin, confirming the Southern America ancestry of the Taıno people of the Caribbean, and that this ancestral populations likely diverged from the Native populations in Mexico and western Colombia over 11 thousand years abo and experienced dramatic bottlenecks.
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Monday, October 28, 2013
1:00 P.M.
Palmer Commons, Great Lakes North Room
