The genetic variants of RANKL/RANK/OPG signal trial in postmenopausal women with osteopenia and osteoporosis

Objectives: Development and differentiation of osteoclasts are regulated by three factors which belong to the family of tumor necrosis factor: RANK, RANKL, OPG. Interaction disorders of the RANKL/RANK/OPG system can be an element of the etiopathogenesis of postmenopausal osteoporosis. Aim of the study: To examine the frequency of alleles and genotypes of four polymorphisms: !163 A > G, !245 T > G, !950 T > C, 1181 G > C in the OPG gene in the group of postmenopausal women and to determine the connection of examined genetic variants with parameters of the bone turnover and progresses of osteoporosis. Material and methods: The study included 310 postmenopausal Caucasian women (139 women with osteoporosis, 107 women with osteopenia, 64 healthy women). The frequency of polymorphisms was examined by polymerase chain reaction and restriction fragment length polymorphism (PCR/RFLP) method. Results: Connecting to !163 A > G polymorphism we have observed the over representation of genotypes contains at least one mutated alleles (AG + GG) in the group with osteoporosis (27.3 vs. 20.3% in controls, ns). Connecting to !245 T > G and 1181 G > C polymorphisms any statistically differences in frequency of particular genotypes were not observed. Analysing !950 T > C polymorphism in women with osteoporosis and osteopenia the comparable frequencies of mutated CC genotypes (27.4 and 22.4 vs. 26.6% in the group with the correct t-score value, p = ns) and C allele (54.3 and 56.1 vs. 54.7%, p = ns) has been found. Any correlation between parameters of bone turnover and frequency of particular genotypes was observed.