Abstract:
:The statistical analysis of genome-wide association studies (GWASs) with multiple diseases and shared controls (SCs) is discussed. The usual method for analyzing data from these studies is to compare each individual disease with either the SCs or the pooled controls which include other diseases. We observed that applying individual association tests can be problematic because these tests may suffer from power loss in detecting significant associations between diseases and single-nucleotide polymorphism or copy number variant. We propose here a two-stage procedure wherein we first apply an overall chi-square test for multiple diseases with SCs; if the overall test is rejected, then individual tests using the chi-square partition method will be applied to each disease against SCs. A real GWAS data set with SCs and a Monte Carlo simulation study are used to demonstrate that the proposed method is more effective and preferable than other existing methods for analyzing data from GWASs with multiple diseases and SCs.
journal_name
Stat Methods Med Resjournal_title
Statistical methods in medical researchauthors
Chen Z,Huang H,Ng HKdoi
10.1177/0962280212474061subject
Has Abstractpub_date
2016-04-01 00:00:00pages
954-67issue
2eissn
0962-2802issn
1477-0334pii
0962280212474061journal_volume
25pub_type
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