A functional SNP upstream of the beta-2 adrenergic receptor gene (ADRB2) is associated with obesity in Oceanic populations

作者：Naka I; Hikami K; Nakayama K; Koga M; Nishida N; Kimura R; Furusawa T; Natsuhara K; Yamauchi T; Nakazawa M; Ataka Y; Ishida T; Inaoka T; Iwamoto S; Matsumura Y; Ohtsuka R; Tsuchiya N; Ohashi J^*

来源：International Journal of Obesity, 2013, 37(9): 1204-1210.

DOI：10.1038/ijo.2012.206

• beta-2 adrenergic receptor gene (ADRB2)
• body mass index (BMI)
• obesity
• Oceanic population
• polymorphism

OBJECTIVE: Obesity is a growing health concern in the Oceanic populations. To investigate the genetic factors associated with adult obesity in the Oceanic populations, the association of single nucleotide polymorphisms (SNPs) of the beta-2 adrenergic receptor (ADRB2) gene with obesity was examined in 694 adults living in Tonga and Solomon Islands. %26lt;br%26gt;RESULTS: A screening for variation in 16 Oceanic subjects detected 17 SNPs in the entire region of ADRB2, of which nine SNPs including two non-synonymous ones, rs1042713 (Arg16Gly) and rs1042714 (Gln27Glu), were further genotyped for all subjects. The rs34623097-A allele, at a SNP located upstream of ADRB2, showed the strongest association with risk for obesity in a logistic regression analysis adjusted for age, sex, and population (P = 5.6 x 10(-4), odds ratio [OR] 2.5, 95% confidence interval [CI] 1.5-4.2). The 27Glu was also significantly associated with obesity in the single-point association analysis (P = 0.013, OR = 2.0, 95% CI = 1.2-3.4); however, this association was no longer significant after adjustment for rs34623097 since these SNPs were in linkage disequilibrium with each other. A copy of the obesity-risk allele, rs34623097-A, led to a 1.6 kg/m(2) increase in body mass index (BMI; defined as weight in kilograms divided by height in meters squared) (P = 0.0019). A luciferase reporter assay indicated that rs34623097-A reduced the transcriptional activity of the luciferase reporter gene by approximately 10% compared with rs34623097-G. An electrophoretic mobility shift assay demonstrated that rs34623097 modulated the binding affinity with nuclear factors. An evolutionary analysis implies that a G%26gt;A mutation at rs34623097 occurred in the Neandertal genome and then the rs34623097-A allele flowed into the ancestors of present-day humans. %26lt;br%26gt;CONCLUSION: The present results suggest that rs34623097-A, which would lead to lower expression of ADRB2, contributes to the onset of obesity in the Oceanic populations.

• 出版日期2013-9