부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tpb.2009.03.005 Byline: Suvajit Samanta (a), Yi-Ju Li (b), Bruce S. Weir (c) Abstract: The coancestry coefficient, also known as the population structure parameter, is of great interest in population genetics. It can be thought of as the intraclass correlation of pairs of alleles within populations and it can serve as a measure of genetic distance between populations. For a general class of evolutionary models it determines the distribution of allele frequencies among populations. Under more restrictive models it can be regarded as the probability of identity by descent of any pair of alleles at a locus within a random mating population. In this paper we review estimation procedures that use the method of moments or are maximum likelihood under the assumption of normally distributed allele frequencies. We then consider the problem of testing hypotheses about this parameter. In addition to parametric and non-parametric bootstrap tests we present an asymptotically-distributed chi-square test. This test reduces to the contingency-table test for equal sample sizes across populations. Our new test appears to be more powerful than previous tests, especially for loci with multiple alleles. We apply our methods to HapMap SNP data to confirm that the coancestry coefficient for humans is strictly positive. Author Affiliation: (a) BARDS, Merck Research Laboratories, P.O. Box 2000, Rahway, NJ 07065-0900, United States (b) Center for Human Genetics, Duke University, Durham, NC 27701, United States (c) Department of Biostatistics, University of Washington, Box 357232, Seattle, WA 98195, United States Article History: Received 17 December 2008