A genome-wide scan using 387 short tandem repeat markers was conducted for obesity among 618 black individuals from 202 families residing in a suburb of Chicago. Evidence for linkage was evaluated with BMI and percent body fat (PBF) using a variance component analysis approach. Suggestive evidence for linkage was found for BMI on chromosome 5 (logarithm of odds [LOD] score = 1.9) and PBF on chromosome 6 (LOD score = 2.7). One additional region on chromosome 3 was linked to these phenotypes at a lower level of significance (LOD score = 1.8 and 0.95 for BMI and PBF, respectively); the linked marker on this chromosome lies in the same region implicated as harboring obesity genes in a previous study of a white population. The replication of linkage evidence using different ethnic groups reinforces the potential significance of this latter candidate region.
Address correspondence and reprint requests to Xiaofeng Zhu, Department of Preventive Medicine and Epidemiology, Loyola University Medical School, Maywood, IL 60153. E-mail:.
Received for publication 26 December 2000 and accepted in revised form 26 October 2001.
IBD, identity-by-descent; LOD, logarithm of odds; MLS, maximum LOD score; PBF, percent body fat; QTL, quantitative trait locus.