The SNP had a genotyping rate >96.5% and was in Hardy-Weinberg equilibrium in both the EA (p = 0.27) and the AA (p = 0.64) samples. The risk allele for rs279871 contained the nucleotide thymine (T) (equivalent to the A nucleotide on the complementary strand in Edenberg et al., 2004). A chi-squared test was employed to examine whether the allele frequency of the T allele was different between high-risk and control families. To ensure an independent sample, one person per family was chosen at random to be included in the test.
