The Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is not associated with obesity or type 2 diabetes mellitus in a large population-based Caucasian cohort.
The beta3-adrenergic receptor (3-BAR) is assumed to play a role in the regulation of energy balance by increasing lipolysis and thermogenesis. A recently detected allelic polymorphism (Trp64Arg polymorphism) has been suggested to contribute to the development of obesity and non-insulin-dependent diabetes mellitus. We examined the prevalence of the two 3-BAR alleles in Germany and looked for associations between 3-BAR genotype and metabolic disorders (obesity and type 2 diabetes mellitus). From over 6450 participants in the Diabetomobile Study, a nationwide epidemiologic study on the prevalence of metabolic disorders (carried out from 1993 to 1996 in Germany), 1259 participants were randomly chosen. The 3-BAR genotype status was determined by 3-BAR gene-specific genomic PCR and consecutive restriction fragment length polymorphism analysis. The frequencies of the different genotypes in the examined cohort were as follows: Trp64/Trp64, 88.3%; Trp64/Arg64, 10.8%; and Arg64/ Arg64, 0.8%. No significant differences between the different genotypes were found when comparing age, body mass index, weight, total and high-density lipoprotein (HDL) cholesterol, fasting insulin, HbA11, and blood pressure; neither did the type 2 diabetes mellitus participants in the different genotype groups differ significantly in terms of age of diabetes onset or HbA11. This is the largest population-based study on the Trp64Arg polymorphism reported yet. The Arg64 allele of the 3-BAR gene was found commonly in Germany. In our cohort, no significant associations between the Arg64 allele and metabolic disorders (e.g. obesity, type 2 diabetes mellitus, dyslipidemia, or hypertension) were detected.
Department of Internal Medicine I, University of Regensburg, Germany.
R
R
Büettner
A
A
Schäffler
H
H
Arndt
G
G
Rogler
J
J
Nusser
B
B
Zietz
I
I
Enger
S
S
Hügl
A
A
Cuk
J
J
Schölmerich
K D
KD
Palitzsch
D000328:Adult; D000375:Aging; D000483:Alleles; D001120:Arginine / Q000235:genetics*; D015992:Body Mass Index; D001833:Body Temperature Regulation; D001835:Body Weight; D002784:Cholesterol / Q000097:blood; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D004734:Energy Metabolism; D005260:Female; D005838:Genotype; D006801:Humans; D008066:Lipolysis; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011897:Random Allocation; D011943:Receptors, Adrenergic, beta / Q000235:genetics*; D014364:Tryptophan / Q000235:genetics*
D011943:Receptors, Adrenergic, beta; D014364:Tryptophan; D001120:Arginine; D002784:Cholesterol