Family Study

Plasma insulin and glucose concentrations are impor-tant quantitative phenotypes related to diabetes and the metabolic syndrome. Reports purporting to identify quantitative trait loci (QTLs) that contribute to the variation in fasting insulin and glucose concentrations are discrepant. As part of the Insulin Resistance Ath-erosclerosis Study (IRAS) Family Study, a genome scan was performed in African-American (n 42) and His-panic (n 90) extended families to identify regions that may contain positional candidate genes for fasting insulin and fasting glucose (n 1,604 subjects). There was significant evidence for linkage of fasting insulin to the short arm of chromosome 17 (logarithm of odds [LOD] 3.30; 54 cM between D17S1294 and D17S1299, P 1.0 104). The strongest evidence for linkage ove