ALLELE AND GENOTYPES FREQUENCIES OF CRP GENE POLYMORPHISM (C1444T; C1846T) IN OSTEOPOROSIS

Abstract

The impact of immune inflammation to bone mineral density has been discussed recently. C-reactive protein is one of the marker of immune inflammation. The CRP base level significantly depends from individual genetic feature. They were founded that some genetic polymorphism of CRP gene associates with the development of cardiovascular diseases. The relationship of cardiovascular diseases and osteoporosis is being discussed also. The aim of study is to examine gene CRP polymorphism (C1444T; C1846T) in women with osteoporosis. Materials and methods. 118 postmenopausal women aged between 60 and 76 were examined. All women were Russian nationality and lived in Transbaikalye region. Osteoporosis was diagnosed in 60 women. Control group consisted of 58 women. The study was conducted according GCP principles and WHO Declaration of Helsinki. Gene polymorphism was determined by PCR method. We used reagents Ltd «Liteh» Moscow. The amplification of gene fragments was determined in thermal cycle (Model «Bis»-M111). Genomic DNA was extracted from peripheral venous blood by reagents «DNA-express-blood». Visualization of the amplification products was performed by electrophoresis in 3% agarose gel. For statistical analysis we used on-line calculator http://gen-exp.ru.calculator_org.php. For comparison of allele and genotypes frequencies we used χ2. It was statistically significant at p<0.05. Results. SNP polymorphisms of locusts 1444 and 1846 gene CRP were discovered in homo and heterozygous condition. The distribution of genotypes of polymorphous locus C1444T and C1846T CRP gene in group of women with osteoporosis and control group corresponded to Hardy - Weinberg law (df=1). It was founded that the relative probability of detection alleles C and T of 1444 locus gene CRP did not differ significantly between control group and group of patients with osteoporosis. -R for C allele was 0,97 (CI95% 0,57-1,69), for T allele OR was 1,04 (CI95% 0,61-1,75). It was shown that the frequency distribution of genotypes CC, TT and CT did not differ significantly. As concerns another point mutations of CRP gene (C1846T), it was founded that the frequency of T allele was 46% in patients with osteoporosis and it was 34% in control group (p=0,06). The relative probability was higher above 1,64 time (CI95% 0,932,77). About the genotypes frequency the next results were got: the homozygous genotype TT met frequently in women with osteoporosis - 18%, in control group they frequency was 34% (p=0,03). The relative probability TT genotype of C1846T locus was higher above 6,27 time (Ci95% 1,33-9,75). It was founded that the heterozygous genotype met rarely in patient with osteoporosis than in control group (57% and 62% accordingly), p=0,03. The homozygous genotype CC met rarely in patients with osteoporosis compared control group