Objective: To observe the correlation between traditional Chinese medicine (TCM) syndromes ("deficiency of qi and yin" and "deficiency of liver yin and kidney yin") and A267G in 5'-untranslated region within exonal of megsin gene, and to search the substantial genetic basis for micro-differentiation of TCM syndromes in primary immunoglobulin A nephropathy (IgAN).
Methods: A total of 120 IgAN cases meeting the diagnostic criteria were enrolled. The sequence of single nucleotide polymorphism (SNP) of A267G in 5'-untranslated region within exonal of megsin gene was tested. The correlation between SNP and TCM syndromes was observed.
Results: There were 83 cases carrying GG genotype, 34 cases carrying GA genotype and 3 cases carrying AA genotype in 120 cases of primary IgAN. There was a high proportion of "deficiency of liver yin and kidney yin" in IgAN cases with AA and GA genotypes, and a high proportion of "deficiency of qi and yin" in IgAN cases with GG genotype (P<0.01). Odds ratio in TCM syndrome distribution between GG genotype and GA plus AA genotype was 9.800, and 95% confidence interval was 3.969-24.199. The discrepancy also resided in IgAN patients with different genders and ages.
Conclusion: A267G in 5'-untranslated region within exonal of the megsin gene may be one of the substantial genetic basis for differentiating "deficiency of liver yin and kidney yin" syndrome and "deficiency of qi and yin" syndrome in primary IgAN.