title: Bivariate genome linkage analysis suggests pleiotropic effects on chromosomes 20p and 3p for body fat mass and lean mass.
abstract: Total body fat mass (TBFM) and total body lean mass (TBLM) are the major components of the human body. Although these highly correlated phenotypic traits are frequently used to characterize obesity, the specific shared genetic factors that influence both traits remain largely unknown. Our study was aimed at identifying common quantitative trait loci (QTLs) contributing to both TBFM and TBLM. We performed a whole genome-linkage scan study in a large sample of 3255 subjects from 420 Caucasian pedigrees. Bivariate linkage analysis was carried out in both the entire sample and gender-specific subsamples. Several potentially important genomic regions that may harbour QTLs important for TBFM and TBLM were identified. For example, 20p12-11 achieved a LOD score of 2.04 in the entire sample and, in the male subsample, two genomic regions, 20p12 (LOD=2.08) and 3p26-25 (LOD=1.92), showed suggestive linkage. In addition, two-point linkage analyses for chromosome X showed suggestive linkages on Xp22 in the entire sample (LOD=2.14) and significant linkage on Xp22 in the female subsample (LOD=3.05). Complete pleiotropy was suggested for 20p12 and 3p26-25 in males. Our results suggest that QTLs on chromosomes 20p12, 3p26-25 and Xp22 may jointly influence TBFM and TBLM. Further fine mapping and gene identification studies for these pleiotropic effects are needed.
authors.affiliation: Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.forename: Peng
authors.initials: P
authors.lastname: Xiao
authors.forename: Yan
authors.initials: Y
authors.lastname: Guo
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Liu
authors.forename: Yu-Fang
authors.initials: YF
authors.lastname: Pei
authors.forename: Tie-Lin
authors.initials: TL
authors.lastname: Yang
authors.forename: Feng
authors.initials: F
authors.lastname: Pan
authors.forename: Yuan
authors.initials: Y
authors.lastname: Chen
authors.forename: Hui
authors.initials: H
authors.lastname: Shen
authors.forename: Lan-Juan
authors.initials: LJ
authors.lastname: Zhao
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Papasian
authors.forename: Betty M
authors.initials: BM
authors.lastname: Drees
authors.forename: James J
authors.initials: JJ
authors.lastname: Hamilton
authors.forename: Hong-Yi
authors.initials: HY
authors.lastname: Deng
authors.forename: Robert R
authors.initials: RR
authors.lastname: Recker
authors.forename: Hong-Wen
authors.initials: HW
authors.lastname: Deng
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D002890:Chromosomes, Human, Pair 20 / Q000235:genetics*; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D041321:Chromosomes, Human, X / Q000235:genetics; D005260:Female; D008040:Genetic Linkage; D015894:Genome, Human; D006801:Humans; D008297:Male; D010375:Pedigree; D040641:Quantitative Trait Loci; D044465:White People / Q000235:genetics