Multiple genes influence BMI on chromosome 7q31-34: the NHLBI Family Heart Study.
The National Heart, Lung, and Blood Institute Family Heart Study (FHS) genome-wide linkage scan identified a region of chromosome 7q31-34 with a lod score of 4.9 for BMI at D7S1804 (131.9 Mb). We report the results of linkage and association to BMI in this region for two independent FHS samples. The first sample includes 225 FHS pedigrees with evidence of linkage to 7q31-34, using 1,132 single-nucleotide polymorphisms (SNPs) and 7 microsatellites. The second represents a case-control sample (318 cases; BMI >25 and 325 controls; BMI <25) derived from unrelated FHS participants who were not part of the genome scan. The latter set was genotyped for 606 SNPs, including 37 SNPs with prior evidence for association in the linked families. Although variance components linkage analysis using only SNPs generated a peak lod score that coincided with the original linkage scan at 131.9 Mb, a conditional linkage analysis showed evidence of a second quantitative trait locus (QTL) near 143 cM influencing BMI. Three SNPs (rs161339, rs12673281, and rs1993068) located near the three genes pleiotrophin (PTN), diacylglycerol (DAG) kinase iota (DGK iota), and cholinergic receptor, muscarinic 2 (CHRM2) demonstrated significant association in both linked families (P = 0.0005, 0.002, and 0.03, respectively) and the case-control sample (P = 0.01, 0.0003, and 0.03, respectively), regardless of the genetic model tested. These findings suggest that several genes may be associated with BMI in the 7q31-34 region.
Laramie
Jason M
JM
Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA. laramiej@gmail.com
Wilk
Jemma B
JB
Williamson
Sally L
SL
Nagle
Michael W
MW
Latourelle
Jeanne C
JC
Tobin
Jennifer E
JE
Province
Michael A
MA
Borecki
Ingrid B
IB
Myers
Richard H
RH
D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001835:Body Weight / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics; D016022:Case-Control Studies; D002874:Chromosome Mapping; D002897:Chromosomes, Human, Pair 7; D016207:Cytokines / Q000235:genetics; D019852:Diacylglycerol Kinase / Q000235:genetics; D005260:Female; D008040:Genetic Linkage; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D008126:Lod Score; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D054555:National Heart, Lung, and Blood Institute (U.S.); D056128:Obesity, Abdominal / Q000235:genetics*; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D043585:Receptor, Muscarinic M2 / Q000235:genetics; D011950:Receptors, Cholinergic / Q000235:genetics; D014481:United States
C487078:CHRM2 protein, human; D002352:Carrier Proteins; D016207:Cytokines; D043585:Receptor, Muscarinic M2; D011950:Receptors, Cholinergic; C066845:pleiotrophin; D019852:Diacylglycerol Kinase