Effects of Trp64Arg mutation in the beta 3-adrenergic receptor gene on weight loss, body fat distribution, glycemic control, and insulin resistance in obese type 2 diabetic patients.
OBJECTIVE
To investigate the effects of Trp64Arg mutation in the beta 3-adrenergic receptor gene on weight loss, body fat distribution, glycemic control, and insulin resistance in obese type 2 diabetic patients.


METHODS
We measured body weight, waist-to-hip ratio (WHR), adjusted resting metabolic rate, fasting blood glucose, fasting serum insulin levels, insulin resistance index (fasting glucose x fasting insulin/22.5), and HbA1c levels before and after 12 weeks of obesity treatment in 61 obese women with type 2 diabetes. The MvaI polymorphism of the beta 3-adrenergic receptor gene was determined by polymerase chain reaction-restriction fragment length polymorphism analysis.


RESULTS
Of obese type 2 diabetic patients, those with the mutation (n = 24) had a higher WHR (P < 0.001), a lower adjusted metabolic rate, and higher blood glucose levels, serum insulin levels, insulin resistance index (P < 0.001), and HbA1c levels (P = 0.016). Furthermore, patients with the mutation had smaller decreases in body weight, WHR, insulin resistance index, and HbA1c levels after the weight-loss program compared with patients without the mutation (n = 37), even though food intake, exercise, and serum thyroid hormone levels were similar in both groups.


CONCLUSIONS
These present findings show that the Trp64Arg allele of the beta 3-adrenergic receptor gene may predict difficulty in losing body weight, lowering WHR, and improving glycemic control and insulin resistance in obese patients with type 2 diabetes.
Sakane
N
N
First Department of Internal Medicine, Kyoto Prefectural University of Medicine, Japan.
Yoshida
T
T
Umekawa
T
T
Kogure
A
A
Takakura
Y
Y
Kondo
M
M
D000328:Adult; D000483:Alleles; D001786:Blood Glucose / Q000032:analysis / Q000235:genetics; D001824:Body Constitution / Q000235:genetics / Q000502:physiology*; D003920:Diabetes Mellitus / Q000235:genetics / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics / Q000503:physiopathology*; D005215:Fasting / Q000097:blood; D005260:Female; D005838:Genotype; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology; D008875:Middle Aged; D009154:Mutation / Q000235:genetics / Q000502:physiology*; D009765:Obesity; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics; D011943:Receptors, Adrenergic, beta / Q000235:genetics*; D022702:Receptors, Adrenergic, beta-3; D015431:Weight Loss / Q000235:genetics / Q000502:physiology
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D011943:Receptors, Adrenergic, beta; D022702:Receptors, Adrenergic, beta-3