Introduction: Klotho has an important role in insulin signaling and the development of ageing-like phenotypes in mice. Recently, the G-395A polymorphism in the promoter region of the human klotho gene has been reported to affect promoter function. It has been also shown to be an independent genetic risk factor for atherosclerotic cardiovascular disease. The aim of this study was to examine the possible role of this polymorphism in the metabolic syndrome.
Subjects and methods: The study population consisted of 32 men with metabolic syndrome aged 63.5±14.8 years and 64 healthy men of similar age. The body mass index and the waist to hip ratio were recorded and blood samples were obtained after overnight fasting for biochemical tests. The G-395A polymorphism was genotyped in peripheral blood leucocytes.
Results: The G-395A genotypes were found to be in Hardy-Weinberg equilibrium in both study groups. Compared with healthy men, men with metabolic syndrome were less frequently carriers of the GG genotype and the G allele (53.1 vs 76.6%, P=0.03 and 73.4 vs 86.7%, P=0.02 respectively). Neither BMI, nor lipid profile was different among genotypes of the G-395A polymorphism in men with metabolic syndrome. However, patients carriers of the GG genotype had less frequently diabetes compared with patients with GA or AA genotype (30.8 vs 69.2%, P=0.03).
Conclusion: The G-395A polymorphism of the klotho gene may be involved in the pathogenesis of metabolic syndrome and glucose metabolism in men.