Heritability was estimated for all traits using Sequential Oligogenic Linkage Analysis Routines (Almasy and Blangero, 1998). The polygenic command was used in Sequential Oligogenic Linkage Analysis Routines, which provides an estimate of the total additive genetic heritability. The software program, QTDT (http://www.sph.umich.edu/csg/abecasis/QTDT/index.html), was used to test for association in our families. Specifically, we used the orthogonal association model (-ao) while modeling environmental, polygenic, and additive major locus effects (-wega) (Abecasis et al., 2000a). Empirical P values were estimated from 1000 Monte Carlo permutations, which makes this test robust to small sample sizes and non-normal data (Abecasis et al., 2000b). To adjust for multiple testing, we used the Benjamini–Hochberg false discovery rate (FDR) procedure to correct for the number of SNPs evaluated across both genes (n=89) and used an FDR-adjusted P value (q value) threshold of 0.05 to determine significance (Benjamini and Hochberg, 1995). SAS 9.1 was used to calculate the FDR q values. We did not adjust for the number of phenotypes tested because there is not an ideal way to properly account for the fact that many of the
