Calcitonin receptor gene polymorphism in Japanese women: Correlation with body mass and bone mineral density

We have identified a polymorphism at position 1377 of the calcitonin recept or (CTR) gene which generates CC, CT, or TT genotype. In this study, the ge notypes of the CTR and their relationship with the body height, the body we ight, the bone mineral density (BMD), and osteocalcin levels were examined in 152 healthy Japanese women aged 16-43 years. The CTR genotypic frequenci es in the Japanese population were 77.0% for CC, 20.4% for CT, and 2.6% for TT. The height, BMD, and osteocalcin levels were not significantly differe nt among these three genotypes. The body weight adjusted for height in thes e three groups was significantly different in the order of TT, CT, and CC ( P = 0.0454 by analysis of covariance). In combined analysis of the VDR geno type (B,b) and the CTR genotype (C,T), the body height was found to be sign ificantly different between CCB and others (P = 0.0236). In addition, analy sis of the CTR genotypic frequency using 64 blood samples from Japanese and 47 blood samples from Caucasians indicated that there was a significant di fference between the two races (P < 0.0001). We found that C allele was pre dominant in the Japanese population, however, Caucasians have an almost equ al ratio of the C and T. In conclusion, the CTR allele is one of the geneti c factors regulating body weight in Japanese women.