Heritability of each of the three clusters was tested and found to be significant only for the Type B/II cluster (h2 =.44, S.E. = 0.18, p<0.01). In the Type B/II cluster, age at interview and gender were significant covariates. Gender (p=0.000006) and age (p= 0.02) together accounted for 5% of the variance respectively. As seen in Fig. 1 and Fig. 2, evidence for linkage was found for the Type B/II cluster vs. no diagnosis, on chromosome 16 (@139 cM, LOD score= 4.4), and on chromosome 19 (@74 cM, LOD score= 6.4). Regions of interest for this phenotype (LOD > 1.5) were also located on chromosome 14, at 122 cM, on chromosome, 21 at 7 cM and on chromosome 22 at 17 cM as seen in Fig. 3 and listed in Table 3.
