Association of myostatin gene polymorphisms with obesity in Chinese north Han human subjects.

Context: Myostatin (MSTN) is a member of the TGF-β superfamily of signal transduction proteins, which plays an important role in muscular growth and lipid metabolism.

Objective: To study the association of myostatin gene polymorphisms with obesity in Chinese north Han human subjects.

Design: 297 healthy and 606 over-weight/obesity Chinese north Han subjects were selected as healthy control group and overweight/obesity group, respectively. The methods of DNA Sequencing, Restriction Fragment Length Polymorphism (RFLP) and TaqMan® probe were used to screen myostatin gene SNPs and clarify genotype in every individual.

Results: Total 11 SNPs in MSTN gene were identified by DNA sequencing and three SNPs including rs35781413 (G/A), rs3791783 (A/G) and rs3791782 (A/G) were selected for further study in total 903 samples. The results showed that the frequency of AA genotype of rs3791783 A/G SNP was significantly higher (56.4% vs. 50.8%) and the frequency GG genotype was significantly lower (3.2% vs. 6.7%) in overweight/obese patients than in normal weight subjects. A logistic regression analysis under a recessive inheritance model (AA+AG vs.GG) demonstrated that the Odd ratio for AA+AG vs.GG were 1.985 (95% CI 1.078-3.643; P=0.029). Among three genotypes of rs3791783, the subjects with AA genotype have much more higher body weight, BMI, waist circumference, TC, TG and LDL-C than those with GG genotype.

Conclusions: Our data firstly suggest that genetic variant rs3791783 A/G in myostatin gene are associated with obesity. The A allele carriers in rs3791783 SNP have an increased susceptibility to obesity compared with the G allele carriers. Participants with AA genotype in rs3791783 SNP site will have higher risk suffered from overweight or obesity than those with GG genotype.