Association Between Bone Mineral Density And Genetic Polymorphisms Of Vitamin D Receptor Gene,calcitonin Receptor Gene In Post-menopause Han Population Of Women From Xinjiang,in China

Objective:To investigate the association of bone mineral density（BMD）with vitamin D receptor（VDR）gene and calcitonin receptor（CTR）gene polymorphisms in Han women from Xinjiang,in China;and to discuss the genetic susceptibility factors of pathogenesis of osteoporosis（OP）.Methods:VDR and CTR genotypes were defined with polymerase chain reaction-restriction fragment length polymophism（PCR-RFLP）,so as to analyze distribution of VDR and CTR polymophisms of 336Han women from Xinjiang,in China.BMD was measured by dual energy X-ray absorptiometry（DEXA）at the lumbar spine(L_2-4),Ward’s triangle,great trochanter,and femoral shaft.Comparing the difference of BMD values of different locations in different genotypes.Results:336 women were included in the study.（1）The frequencies of VDR and CTR genes and alleles in the study subjects were in accordance with the Hardy-weinberg equilibrium law.Subjects were divided into two groups according to T values:osteoporosis group（90 cases）and non-bone group（246 cases）.The individual genotypes of VDR receptor gene and CTR receptor gene and their allele frequency were analyzed.The frequency distribution of VDR and CTR genes was not statistically significant（P>0.05）.（2）There was a close relationship between age and BMD values of various sites.As the age decreased,the BMD value of each site decreased,and there was a negative correlation between them（P<0.05）.BMI was closely related to BMD values of various sites.As the BMD was increased,Bone mineral density was increased in all sites and there was a positive correlation（P<0.05）.（3）The VDR-BB type（4 cases）in the osteoporosis group showed a higher degree of BMD compared with VDR-Bb（12 cases）and VDR-bb type（74 cases）,there was no significant difference between the groups（P>0.05）.There was no significant difference in the BMD values??between the CTR-CC type（73 cases）and the CTR-CT type（17 cases）（P>0.05）;non-osteoporosis group VDR The BMD value of-bb type（216 cases）was higher in the 2-4,ward’s triangle of the lumbar spine than in the VDR-Bb type（24 cases）,the difference was statistically significant（P<0.05）;The BMD value of VDR-bb type（216 cases）was higher in the trochanter and femoral shaft than in the VDR-Bb type（24 cases）,and the difference was statistically reduced（0.05<P<0.1）;The BMD value of the CTR-CT type（43 cases）detected in the Ward’s triangle was higher than that of the CTR-CC type（203 cases）at the site,and the difference was statistically significant（P<0.05）;There was no significant difference in the BMD values of the VDR-CTR complex genotypes detected in the osteoporosis group.There was no significant difference between the composite genotypes（P>0.05）;CCBb type（19cases）was detected in the non-osteoporosis group.In the non-osteoporotic group,the BMD values of the CCBb type（19 cases）were lower than CCbb type（178 cases）,CCBB type（6 cases）,and CTBb type（5cases）CTbb type in the lumbar 2-4,ward’s triangles（38 cases）,the difference was significant（P<0.05）,also lower than the other types in the large trochanter,femoral shaft,the statistical analysis of the differences have a decreasing trend（0.05<P<0.1）.Conclusion:Age and BMI was closely related to the change of BMD;Bb genotype of VDR was associated with lower BMD.Compound CCBb genotype may be regarded as a genetic marker to predict the risk of osteoporosis in Han women from Xinjiang.