Association between calcium-Sensing receptor gene polymorphisms and urinary calcium stone formation in the Han Chinese population from a High-Altitude region (Kunming) in China.

This case-control study investigated the association between calcium-sensing receptor (CaSR) gene polymorphisms and calcium-containing kidney stone susceptibility in 100 patients and 100 matched healthy controls from the Kunming Han Chinese population. Genotyping of three CaSR loci (rs1042636, rs1801725, and rs1801726) was performed using SNaPshot technology. The rs1801725 GT genotype significantly increased stone formation risk (odds ratio = 1.50, 95% confidence interval: 1.10-2.00, P = 0.042) and was associated with elevated 24-hour urinary calcium excretion compared with controls (10.683 ± 2.535 vs. 7.436 ± 1.742 mmol/24 h, P = 0.002), suggesting impaired renal tubular calcium reabsorption as the underlying mechanism. No significant association was found for rs1042636, while rs1801726 exhibited complete monomorphism (100% CC genotype) across all samples. This study provides the first evidence that the CaSR rs1801725 GT genotype serves as an independent genetic risk marker for urinary calcium stones in the Kunming Han Chinese population. Future research should integrate additional calcium transport pathway genes to develop polygenic risk prediction models and elucidate gene-environment interactions in stone pathogenesis.