Comparison of linkage and association strategies for quantitative traits using the COGA dataset

Genome scans using dense single-nucleotide polymorphism ( SNP) data have recently become a reality. It is thought that the increase in information content for linkage analysis as a result of the denser scans will help refine previously identified linkage regions and possibly identify new regions not identifiable using the sparser, microsatellite scans. In the context of the dense SNP scans, it is also possible to consider association strategies to provide even more information about potential regions of interest. To circumvent the multiple-testing issues inherent in association analysis, we use a recently developed strategy, implementedin PBAT, which screens the data to identify the optimal SNPs for testing, without biasing the nominal significance level. We compare the results from the PBAT analysis to that of quantitative linkage analysis on chromosome 4using the Collaborative Study on the Genetics of Alcoholism data, as released through Genetic AnalysisWorkshop 14.