Sirikanlaya Sookkhee. Efficiency of Single SNP and SNP-set analysis in genome-wide association studies. Doctoral Degree(Applied Statistics). King Mongkut's University of Technology North Bangkok. Central Library. : King Mongkut's University of Technology North Bangkok, 2018.
Efficiency of Single SNP and SNP-set analysis in genome-wide association studies
Abstract:
The objective of this research is to develop and evaluate analytical methods to test an association between a single SNP and an SNP-set with the disease outcome. We evaluate 3 methods which are single SNP analysis, Sequence Kernel Association Test (SKAT), and the recently proposed Generalized Higher Criticism (GHC). Single SNP analysis, which is commonly used as a basis for comparing the efficiency of alternative methods, constructs a p-value for each marker and adjusts the hypothesis tests for multiple testing. SKAT tests the association between a constructed SNP-set and disease outcome by grouping the effect of markers in the SNP-set. On the other hand, GHC is another grouping technique that instead uses single SNP test statistics and their correlation matrix to construct a new test statistic. The simulated data used in this research were constructed from a control data set in a study of Crohn's disease. True positive (TP) and false positive rate (FP) were evaluated under different genetic models for disease with significant thresholds adjusted for multiple hypothesis testing based on the permutation method. The findings are mixed with all 3 methods giving similar TP rates under some disease models and different rates for other models. The single SNP analysis has FP rates comparable with GHC while SKAT's rates are consistently highest. Overall, GHC is shown to be preferable in terms of error rates, but it is disadvantageous in terms of computational efficiency.