title: A whole genome linkage scan identifies multiple chromosomal regions influencing adiposity-related traits among Samoans.
abstract: We conducted a genome-wide scan in 46 pedigrees, with 671 phenotyped adults, from the independent nation of Samoa to map quantitative trait loci (QTLs) for adiposity-related phenotypes, including body mass index (BMI), abdominal circumference (ABDCIR), percent body fat (%BFAT), and fasting serum leptin and adiponectin. A set of 378 autosomal and 14 X chromosomal microsatellite markers were genotyped in 572 of the adults. Significant genetic correlations (0.82-0.96) were detected between pairs of BMI, ABDCIR, %BFAT and leptin. Suggestive linkages were found on 13q31 (LOD = 2.30 for leptin, LOD = 2.48 for %BFAT, LOD = 2.04 for ABDCIR, and LOD = 2.09 for BMI) and on 9p22 (LOD = 3.08 for ABDCIR and LOD = 2.53 for %BFAT). Furthermore, bivariate linkage analyses indicated that the genetic regions on 9p22 (bivariate LOD 2.35-3.10, LOD(eq) (1df) 1.88-2.59) and 13q31 (bivariate LOD 1.96-2.64, LOD(eq) 1.52-2.21) might harbor common major genes with pleiotropic effects. Other regions showing suggestive linkage included 4q22 (LOD = 2.95) and 7p14 (LOD = 2.64) for %BFAT, 2q13 for adiponectin (LOD = 2.05) and 19q12 for BMI-adjusted leptin (LOD = 2.03). Further fine mapping of these regions may help identify the genetic variants contributing to the development of obesity in Samoan adults.
authors.affiliation: Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: F
authors.initials: F
authors.lastname: Dai
authors.forename: G
authors.initials: G
authors.lastname: Sun
authors.forename: K
authors.initials: K
authors.lastname: Aberg
authors.forename: E D
authors.initials: ED
authors.lastname: Keighley
authors.forename: S R
authors.initials: SR
authors.lastname: Indugula
authors.forename: S T
authors.initials: ST
authors.lastname: Roberts
authors.forename: D
authors.initials: D
authors.lastname: Smelser
authors.forename: S
authors.initials: S
authors.lastname: Viali
authors.forename: L
authors.initials: L
authors.lastname: Jin
authors.forename: R
authors.initials: R
authors.lastname: Deka
authors.forename: D E
authors.initials: DE
authors.lastname: Weeks
authors.forename: S T
authors.initials: ST
authors.lastname: McGarvey
mesh_terms: D050154:Adiposity / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D020022:Genetic Predisposition to Disease; D015894:Genome, Human; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics; D010375:Pedigree; D018947:Samoa