Genetic variants of the MIR31HG gene are related to a risk of IgA nephropathy.

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Previous studies reveal that genetic factors play a crucial role in IgAN progression. This study was conducted to investigate the association between MIR31HG variants and IgAN risk. A total of 836 subjects were recruited to detect the relationship of MIR31HG variants with IgAN susceptibility. Odds ratios (OR) and 95% confidence intervals (CI) were computed to evaluate the associations. Multifactor dimensionality reduction was performed to analyze the SNP-SNP interaction with IgAN risk. Our study showed that rs1332184 and rs55683539 significantly related to an increased risk of IgAN (OR 1.34, p = 0.041; OR 1.39, p = 0.025). Stratified analyses indicated rs72703442, rs55683539, and rs10965064 exhibited strongly enhanced risk of IgAN in age ≤ 35 years (OR 1.55, p = 0.023; OR 1.60, p = 0.012; OR 1.46, p = 0.037). Besides, we found rs1332184, rs55683539 and rs2181559 significantly increased the susceptibility of IgAN in males (OR 1.71, p = 0.003; OR 1.44, p = 0.042; OR 1.60, p = 0.010). We also observed that rs1332184 could enhance IgAN risk for Lee's grade ≥ III (OR 1.39, p = 0.045). Rs55683539 significantly increased a risk of IgAN (OR 1.58, p = 0.027), while rs2025327 had a lower risk of IgAN in Lee's grade < III (OR 0.46, p = 0.007). Interestingly, we found rs72703442 polymorphism was related to hemoglobin (p = 0.043), and rs10965064 was associated with Urine red blood cell (p = 0.040). Our study proposed that MIR31HG polymorphisms associate with susceptibility to IgAN in Chinese population.