title: The Arg16Gly polymorphism of human beta2-adrenoreceptor is associated with type 2 diabetes in Taiwanese people.
abstract: OBJECTIVE
  The significance of the association of amino terminal polymorphisms in beta2-adrenoreceptor (ADRB2) with obesity and type 2 diabetes is controversial and differs among ethnic groups. In this study, the association of ADRB2 with risk and age of onset of type 2 diabetes has been examined in a Taiwanese population.
  
  
  METHODS
  The study design is a case-control study to investigate the impact of the two amino acid polymorphisms in ADRB2.
  
  
  METHODS
  This study includes 130 patients with type 2 diabetes [female : male = 1 : 1, age: 52.4 +/- 10.0 years; body mass index (BMI): 24.2 +/- 2.9 kg/m2; mean +/- SD] and 130 controlled subjects matched for gender, age and BMI with normal glucose tolerance (female : male = 1 : 1, age: 51.7 +/- 10.6 years; BMI: 23.9 +/- 2.7 kg/m2). The Arg16Gly and Gln27Glu polymorphisms of ADRB2 were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. The genotypic and allelic frequencies between two groups were compared and the relationship between the genotypes and clinical phenotypes was examined.
  
  
  RESULTS
  A difference in genotypic frequency in the Arg16Gly polymorphism was noted between groups in this gender-, age- and BMI-matched case-control study (P = 0.039). Multivariate regression analysis revealed that the Arg16Gly polymorphism was the only independent factor for development of type 2 diabetes (P = 0.021). In addition, we utilized the log-rank test to compare the differences in age of onset between wild-type and nonwild-type polymorphisms. The Arg16Gly polymorphism was independently associated with age of onset in type 2 diabetes (P = 0.017). There was no difference in the Gln27Glu polymorphism between diabetic and control groups in this study.
  
  
  CONCLUSIONS
  In a Taiwanese population, homozygosity of Arg16 in the ADRB2 gene was associated with a higher frequency (odds ratio 1.87, 95% confidence interval 1.34-2.40) for development of type 2 diabetes. Moreover, this polymorphism was also associated with an earlier onset of type 2 diabetes. However, the Glu27Gln polymorphism had no impact on either BMI or type 2 diabetes in a Taiwanese population.
authors.affiliation: Department of Internal Medicine, En-Chu-Kung Hospital, San-Shia Town, Taipei Hsien, Taiwan.
authors.forename: Tien-Jyun
authors.initials: TJ
authors.lastname: Chang
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Tsai
authors.forename: Yi-Der
authors.initials: YD
authors.lastname: Jiang
authors.forename: Borheng
authors.initials: B
authors.lastname: Lee
authors.forename: Kuan-Ching
authors.initials: KC
authors.lastname: Lee
authors.forename: Jin-Yu
authors.initials: JY
authors.lastname: Lin
authors.forename: Ken C
authors.initials: KC
authors.lastname: Chiu
authors.forename: Tong-Yuan
authors.initials: TY
authors.lastname: Tai
authors.forename: Lee-Ming
authors.initials: LM
authors.lastname: Chuang
mesh_terms: D000328:Adult; D017668:Age of Onset; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology* / Q000235:genetics*; D005260:Female; D006720:Homozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*; D013624:Taiwan
chemical_list: D018343:Receptors, Adrenergic, beta-2