Adaptive Set‐Based Methods for Association Testing

ABSTRACT
With a typical sample size of a few thousand subjects, a single genome‐wide association study (GWAS) using traditional one single nucleotide polymorphism (SNP)‐at‐a‐time methods can only detect genetic variants conferring a sizable effect on disease risk. Set‐based methods, which analyze sets of SNPs jointly, can detect variants with smaller effects acting within a gene, a pathway, or other biologically relevant sets. Although self‐contained set‐based methods (those that test sets of variants without regard to variants not in the set) are generally more powerful than competitive set‐based approaches (those that rely on comparison of variants in the set of interest with variants not in the set), there is no consensus as to which self‐contained methods are best. In particular, several self‐contained set tests have been proposed to directly or indirectly “adapt” to the a priori unknown proportion and distribution of effects of the truly associated SNPs in the set, which is a major determinant of their power. A popular adaptive set‐based test is the adaptive rank truncated product (ARTP), which seeks the set of SNPs that yields the best‐combined evidence of association. We compared the standard ARTP, several ARTP variations we introduced, and other adaptive methods in a comprehensive simulation study to evaluate their performance. We used permutations to assess significance for all the methods and thus provide a level playing field for compari...

Source: Genetic Epidemiology - December 28, 2015 Category: Epidemiology Authors: Yu‐Chen Su, William James Gauderman, Kiros Berhane, Juan Pablo Lewinger Tags: Research Article Source Type: research