title: High-resolution genome-wide linkage mapping identifies susceptibility loci for BMI in the Chinese population.
abstract: The genetic loci affecting the commonly used BMI have been intensively investigated using linkage approaches in multiple populations. This study aims at performing the first genome-wide linkage scan on BMI in the Chinese population in mainland China with hypothesis that heterogeneity in genetic linkage could exist in different ethnic populations. BMI was measured from 126 dizygotic twins in Qingdao municipality who were genotyped using high-resolution Affymetrix Genome-Wide Human SNP arrays containing about 1 million single-nucleotide polymorphisms (SNPs). Nonparametric linkage analysis was performed with Merlin software package for linkage analysis using variance components approach for quantitative trait loci mapping. We identified a strong linkage peak at the end of chromosome 7 (7q36 at 186 cM) with a lod score of 4.06 which overlaps with that reported by a large multicenter study in western countries. Multiple loci showing suggestive linkage were found on chromosome 1 (lod score 2.38 at 242 cM), chromosome 8 (2.48 at 95 cM), and chromosome 14 (2.2 at 89.4 cM). The strong linkage identified in the Chinese subjects that is consistent with that found in populations of European origin could suggest the existence of evolutionarily preserved genetic mechanisms for BMI whereas the multiple suggestive loci could represent genetic effect from gene-environment interaction as a result of population-specific environmental adaptation.
authors.affiliation: Department of Public Health, Qingdao University Medical College, Qingdao, China. zhangdf1961@126.com
authors.forename: Dong Feng
authors.initials: DF
authors.lastname: Zhang
authors.forename: Zengchang
authors.initials: Z
authors.lastname: Pang
authors.forename: Shuxia
authors.initials: S
authors.lastname: Li
authors.forename: Mads
authors.initials: M
authors.lastname: Thomassen
authors.forename: Shaojie
authors.initials: S
authors.lastname: Wang
authors.forename: Wengjie
authors.initials: W
authors.lastname: Jiang
authors.forename: Jacob v B
authors.initials: Jv
authors.lastname: Hjelmborg
authors.forename: Torben A
authors.initials: TA
authors.lastname: Kruse
authors.forename: Kirsten O
authors.initials: KO
authors.lastname: Kyvik
authors.forename: Kaare
authors.initials: K
authors.lastname: Christensen
authors.forename: Qihua
authors.initials: Q
authors.lastname: Tan
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics*; D015992:Body Mass Index; D002681:China / Q000453:epidemiology; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008126:Lod Score; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000235:genetics*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D018709:Statistics, Nonparametric; D014429:Twins, Dizygotic / Q000235:genetics