[Association of α-actinin-3 gene polymorphism and muscle strength of postmenopausal women].

To explore the association between α-actinin-3 (3) polymorphism and muscle strength in postmenopausal women. Five hundred and ninety-eight postmenopausal women with an average of (62.9±7.0) years old in Dongcheng District of Beijing were included. The 3 polymorphism including rs540874, rs618838 and rs2229456 were genotyped by Sequenom Mass Array to explore their associations with muscle strength. One hundred and sixty-three of them were trained with regular Tai chi movement while 271 were administered with elemental calcium 600 mg/d combined with Vitamin D 800 U/d or calcitriol 0.25 μg/d for 2 years. Association between changes of muscle strength and 3 polymorphism were analyzed. The rs540874 genotypes were found to be significantly associated with chair stand test[GG (9.02±3.85) s vs GA (9.27±4.14) s vs AA (9.68±5.00) s, =0.015]. Right grip strength in women with G allele were likely to be higher compared with A allele, but it was not statistically significant (=0.056). Multiple linear regression showed that the chair stand test of AA genotype was statistically longer than that of GG and GA genotype (β=2.639, 95% : 1.632-4.646, =0.010). The associations between rs618838, rs2229456 genotypes and muscle strength of both lower and upper limbs were not significant (all >0.05). In addition, muscle strength of lower limbs of patients with rs540874 genotyped with G allele, rs618838 genotyped with C allele and rs2229456 genotyped with A allele increased significantly after enhanced exercise and vitamin D supplementation (all <0.05). The rs540874 polymorphism of 3 gene was associated with the muscle function of lower limb in postmenopausal women. The improvement of muscle strength after intervention were possibly correlated with rs540874, rs618838 and rs2229456 polymorphisms.