Aim: To identify risk groups for calcium oxalate urolithiasis among healthy individuals and patients with urolithiasis in the Russian population using molecular genetics.
Materials and methods: The study comprised 72 patients with calcium oxalate urolithiasis (study group) and 189 healthy adults from the general Russian population (control group). The study group consisted of 39 (54.2%) men and 33 (45.8%) women. The mean age of urolithiasis patients was 41.5+/-12.4 years. Analysis of polymorphic variants of 8 candidate urolithiasis genes: tumor necrosis factor 11B (TNFRSF11B, rs3134057), -subunit of the nuclear estrogen receptor (ESR1, rs851982), Cloto gene (KL, rs526906), vitamin D receptor (VDR, rs1540339 ), an extracellular calcium-sensing receptor (CASR, rs2202127), membrane anion transporter family 26 (SLC26A6, rs2310996), tumor necrosis factor 11 (TNFSF11, rs9525641), the calcium release-activated calcium modulator 1 (ORAI1, rs7135617) in two groups was performed by real-time PCR using Applied Biosystems test. Statistical analysis was performed using Fishers angular transformation and 2.
Results: In the polymorphism of the ORAI1 gene (rs7135617), the differences in the frequencies of the GG genotype and the G allele in the control sample and in the sample of patients with calcium oxalate urolithiasis were significant: p=0.0004 and p=0.001, respectively. No statistically significant differences in the genotype and allele frequencies were found in the remaining seven gene polymorphisms.
Conclusions: Healthy individuals and patients with urolithiasis in the Russian population who have the GG genotype and/or the G allele of the polymorphism of the ORAI1 gene (rs7135617) represent risk groups for the formation of calcium oxalate stones.
Keywords: calcium oxalate urolithiasis; gene polymorphism; genetic risk factors; urolithiasis.