Associations of the PTEN −9C>G polymorphism with insulin sensitivity and central obesity in Chinese.

Abstract: Background: Phosphatase and tensin homolog on chromosome 10 gene (PTEN) is known as a tumor-suppressor gene. Previous studies demonstrated that PTEN dysfunction affects the function of insulin. However, investigations of PTEN single nucleotide polymorphisms (SNPs) and IR-related disease associations are limited. The aim of the present study was to investigate whether its polymorphism could be involved in the risk of metabolic syndrome (MetS). Methods: The genotype frequency of PTEN −9C>G polymorphism was determined by using a Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) method in 530 subjects with MetS and 202 healthy control subjects of the Han Ethnic Chinese population in a case–control analysis. Results: The PTEN −9C>G polymorphism was not associated with MetS or its hyperglycemia, hypertension and hypertriglyceridemia components. In the control individuals aged <60years or ≥60years, the CG genotype individuals had lower insulin sensitivity than CC individuals (P <0.05). In the <60-year-old MetS group and normal glucose tolerance (NGT) subgroup, the CG individuals had lower insulin sensitivity and higher waist circumference (WC) and waist-height-ratio (WHtR) than CC individuals (P <0.05). Multiple linear regression analysis showed that the PTEN polymorphism (P =0.001) contributed independently to 4.2% (adjusted R2) of insulin sensitivity variance (estimated by Matsuda ISI), while age (P =0.004), gender (P =0.000) and the PTEN polymorphism (P =0.032) contributed independently to 5.6% (adjusted R2) of WHtR variance. Conclusions: The CG genotype of PTEN −9C>G polymorphism was not associated with MetS and some of its components as well. However, it may not only decrease insulin sensitivity in the healthy control and MetS in pre-elderly or NGT subjects, but may also increase the risk of central obesity among these MetS individuals. [Copyright &y& Elsevier]