Abstract
The candidate-gene approach can be used to locate and identify genetic variations that are associated with a particular phenotype. This gene-centric approach assumes that there exists important genetic variation within genes that can influence health. Identifying known genes which are candidates for the phenotype of interest can be accomplished using existing knowledge about biology or using findings from genome-wide association studies. Genetic variation can be characterized locally by single nucleotide polymorphisms (SNPs) or insertion-deletions, or it can be characterized more broadly in terms of haplotypes and diplotypes, which usually need to be inferred statistically. As an example, we present a candidate-gene approach to identify novel associations between variation in 24 clotting genes and the risk of incident venous thrombosis.