Three SNPs of FCRL3 and one SNP of MTMR3 are associated with immunoglobulin A nephropathy risk.

PURPOSE: Immunoglobulin A nephropathy (IgAN) is determined by a combination of multiple genetic and environmental factors, but its etiology and pathogenesis are not well understood. We aim to determine whether variations in FCRL3 and MTMR3 correlate with IgAN risk indices in Chinese Han people.

METHODS: Eight single nucleotide polymorphisms (SNPs) of FCRL3 and MTMR3 were genotyped, and association analysis was performed. A total of 426 patients with IgAN and 498 healthy individuals, serving as the control group, were recruited for this association study.

RESULTS: There were significant associations between FCRL3 rs11264793 (OR = 0.78; 95 % CI = 0.63-0.98; p = 0.029), rs11264794 (OR = 0.81; 95 % CI = 0.67-0.98; p = 0.026) and rs7522061 (OR = 0.79; 95 % CI = 0.65-0.95; p = 0.012) and decreased risk of IgAN according to allele model results. Under genetic models, FCRL3 and MTMR3 were associated with the risk of IgAN. Interestingly, FCRL3 reduced the IgAN susceptibility only in females, while MTMR3 was a risk factor for IgAN only in males. In addition, FCRL3 rs11264793 and rs7522061 were significantly associated with a decreased risk of IgAN in different disease grades. Moreover, the haplotypes ACC (p = 0.02) and CTC (p = 0.017) of LD block rs11264794/rs7522061/rs11264799 in the FCRL3 gene were significantly associated with a decreased risk of IgAN.

CONCLUSIONS: We suggest that three SNPs of FCRL3 were associated with a decreased risk of IgAN, while one SNP of MTMR3 was associated with an increased risk of IgAN in Chinese Han populations. These findings may be useful in the development of early prognostics for IgAN.