Genome Scan for Human Obesity and Linkage to Markers in 20q13

Abstract

Obesity is a highly prevalent, multigenic trait that predicts increased morbidity and mortality. Here we report results from a genome scan based on 354 markers in 513 members of 92 nuclear families ascertained through extreme obesity and normal body weight. The average marker interval was approximately 10 cM. We examined four correlated obesity phenotypes, including the body-mass index (BMI) (both as a quantitative trait and as a discrete trait with a threshold of BMI > or /=30 kg/m2) and percentage of fat (both as a quantitative trait and as a discrete trait with a threshold of 40%) as assessed by bioelectrical impedance. In the initial stage of the genome scan, four markers in 20q gave positive evidence for linkage, which was consistent across most obesity phenotypes and analytic methods. After saturating 20q with additional markers (25 markers total) in an augmented sample of 713 members from 124 families, we found linkage to several markers in a region, 20q13, previously implicated in both human and animal studies. Three markers (D20S107, D20S211, and D20S149) in 20q13 had empirical P values (based on Monte Carlo simulations, which controlled for multiple testing) < or /=. 01 for single-point analysis. In addition, the parametric, affecteds-only analysis for D20S476 yielded a LOD score of 3.06 (P=. 00009), and the affected-sib-pair test yielded a LOD score of 3.17 (P=.000067). Multipoint analyses further strengthened and localized these findings. This region includes several plausible candidate genes for obesity. Our results suggest that one or more genes affecting obesity are located in 20q13.

Sex-specific findings from a genome-wide linkage analysis of human fatness in non-Hispanic whites and African Americans: The HyperGEN Study

“…Early reports indicated relatively consistent findings for 10p from three studies of US European American, French, and German cohorts. [19][20][21]63 Subsequently, several other reports on obesity-related phenotypes have found signals in the same or nearby chromosomal regions, but also including signals on 1q, 12 12,27 None of these studies have reported sex-specific linkage findings.…”

Interaction between obesity-susceptibility loci in chromosome regions 2p25-p24 and 13q13-q21

“…The recruitment processes have been described previously. 26,27 After obtaining informed consent, the probands and their biological parents and full siblings were measured for weight, height, waist circumference, percent body fat and other anthropometric measurements. Blood samples were also collected.…”

Sequencing and characterization of lncRNAs in the breast muscle of Gushi and Arbor Acres chickens

“…Interestingly, PTPN1, the gene coding for PTP-1β, is located in a genomic region that has been identified in numerous linkage studies as a QTL for obesity and diabetes (Ghosh et al 1999;Lee et al 1999;Soro et al 2002). PTP-1β affects plasma lipid levels and might result in obesity and hypertension in Japanese and Chinese populations.…”