No evidence for involvement of alleles of the 825-C/T polymorphism of the G-protein subunit beta 3 in body weight regulation.
The 825-C/T polymorphism of the beta 3 subunit of the heterotrimeric G protein gene (GNB3) has been shown to be associated with essential hypertension in humans. Recently, it was also reported that the 825-T allele has a higher frequency in obese than non-obese hypertensives suggesting that the primary effect of this allele is on body weight. The association to hypertension might merely be a secondary effect of the higher weight of the respective allele carriers. To investigate an involvement of the 825-T allele in body weight regulation in young individuals, we evaluated allele frequencies in 440 extremely obese children and adolescents (82.9% had a body mass index [BMI] > or = 99th percentile), 51 obese students (BMI > or = 90th percentile), 110 normal weight students (BMI between 40th and 60th percentile) and 144 underweight students (BMI < or = 15th percentile). The study groups were genotyped by polymerase chain reaction with subsequent restriction fragment length polymorphism analysis (PCR-RFLP). The one-sided Yates-corrected chi(2)-test and the Cochran-Armitage trend test for association were performed. Tests for association were negative. The 825-T allele frequencies were similar in the four study groups belonging to different weight ranges (extreme early onset obesity: 0.29; obesity: 0.28; normal weight: 0.35; underweight: 0.32). Similarly, genotype frequencies did not differ between the groups. We concluded that the 825-T allele of the GNB3 does not play a major role in weight regulation in German children, adolescents and young adults.
Hinney
A
A
Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Germany. Anke.Hinney@med.uni-marburg.de
Geller
F
F
Neupert
T
T
Sommerlad
C
C
Gerber
G
G
Görg
T
T
Siegfried
W
W
Goldschmidt
H
H
Remschmidt
H
H
Ziegler
A
A
Hebebrand
J
J
D000293:Adolescent; D000328:Adult; D000483:Alleles; D015992:Body Mass Index; D001835:Body Weight / Q000235:genetics*; D002648:Child; D005260:Female; D005838:Genotype; D005858:Germany; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics*; D006801:Humans; D008297:Male; D009765:Obesity / Q000235:genetics; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length
D020962:Heterotrimeric GTP-Binding Proteins