Association between KCNQ1 genetic variants and obesity in Chinese patients with type 2 diabetes.
OBJECTIVE
There is evidence of overlap between susceptibility loci for type 2 diabetes and obesity. The aim of this study is to explore the association between the established type 2 diabetes locus KCNQ1 and obesity in Han Chinese.


METHODS
We recruited 6,667 and 6,606 diabetic case-control samples from Shanghai and Hong Kong, respectively. Of the samples, 7.5% and 6.3% were excluded because of genotyping failure or data missing in the association analyses of rs2237892 and rs2237895 with obesity/BMI, respectively.


RESULTS
We found that rs2237892 was associated with lower BMI and lower incidence of overweight/obesity in diabetic patients from Hong Kong (BMI, β = -0.0060 per diabetes risk C allele for log(10)BMI [95% CI -0.0088, -0.0032; p = 2.83 × 10(-5)]; overweight/obesity, OR 0.880 for C allele [95% CI 0.807, 0.960; p = 0.004]) and in the meta-analysis of cases from the two regions (BMI, combined β = -0.0048 per C allele for log(10)BMI [95% CI -0.0070, -0.0026; p = 2.20 × 10(-5)]; overweight/obesity, combined OR 0.890 for C allele [95% CI 0.830, 0.955; p = 0.001]). rs2237895 was also related to decreased BMI (combined β = -0.0042 per diabetes risk C allele for log(10)BMI [95% CI -0.0062, -0.0022; p = 4.30 × 10(-5)]). A significant association with waist circumference was detected for rs2237892 in the pooled analyses (β = -0.0026 per C allele for log(10)[waist circumference] [95% CI -0.0045, -0.0007; p = 0.007]). However, neither an association with the risk of being overweight or obese nor associations with quantitive traits were detected for rs2237892 or rs2237895 in controls.


CONCLUSIONS
Our findings indicate that KCNQ1 is associated with obesity in Chinese patients with type 2 diabetes.
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
W
W
Yu
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.
R C
RC
Ma
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
C
C
Hu
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.
W Y
WY
So
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
R
R
Zhang
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
C
C
Wang
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.
C H
CH
Tam
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.
J S
JS
Ho
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
J
J
Lu
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
F
F
Jiang
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
S
S
Tang
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.|Wake Forest University School of Medicine, Winston-Salem, NC, USA.
M C
MC
Ng
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
Y
Y
Bao
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
K
K
Xiang
Department of Endocrinology and Metabolism, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China. wpjia@sjtu.edu.cn.
W
W
Jia
Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China. jchan@cuhk.edu.hk.
J C N
JCN
Chan
D000483:Alleles; D044466:Asian People / Q000235:genetics*; D015992:Body Mass Index; D016022:Case-Control Studies; D002681:China; D015897:Comorbidity; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000235:genetics*; D005838:Genotype; D006801:Humans; D015994:Incidence; D051657:KCNQ1 Potassium Channel / Q000235:genetics*; D009765:Obesity / Q000453:epidemiology* / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors
D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human