Association of breast cancer-related microRNA polymorphisms with idiopathic primary ovarian insufficiency

Objective: The aim of our study was to investigate whether breast cancer-related microRNA polymorphisms are associated with primary ovarian insufficiency (POI) risk. Methods: Four breast cancer-related microRNA polymorphisms (miR-27aA > G [rs895819], miR-135bC > T [rs74141216], miR-423C > A [rs6505162], and miR-608G > C [rs4919510]) were genotyped in 136 women with idiopathic POI and 224 controls of Korean ethnicity using polymerase chain reaction-restriction fragment length polymorphism analysis. Differences in genotype frequencies between cases and controls were compared. Odds ratios and 95% CIs were determined as measures of the strength of association between genotype and POI. Results: Two haplotypes (G-C-A-G and A-T-C-C) of miR-27a/miR-135b/miR-423/miR-608 were associated with increased POI risk. The haplotypes G-A-G of miR-27a/miR-423/miR-608 and A-T-C of miR-27a/miR-135b/miR-608 were associated with higher POI risk, whereas the G-T haplotype of miR-27a/miR-135b was associated with decreased POI risk. The association between POI risk and the G-A-G haplotype of miR-27a/miR-423/miR-608 remained significant after false discovery rate correction for multiple comparisons. The combined genotypes AA/CT/CC/CC, AG/CC/CA/GC, GG/CC/CC/CC, and GG/CC/CA/GG of miR-27a/miR-135b/miR-423/miR-608 were also associated with higher POI risk. Increased POI risk was observed in combined genotypes GG/CC/GG of miR-27a/miR-135b/miR-608; AA/CC/GC, AG/CA/GC, GG/CC/GG, GG/CC/CC, and GG/CA/GG of miR-27a/miR-423/miR-608; and GG/GG of miR-27a/miR-608; however, these associations were not significant after false discovery rate correction. None of the four microRNA polymorphisms alone was associated with POI risk. Conclusions: Our data suggest that breast cancerYrelated microRNA polymorphisms, including miR-27aA 9 G, miR-423C 9 A, and miR-608G 9 C, are associated with increased POI risk via interactions between miR-27aG, miR-423A, and miR-608G variants. However, our results should be interpreted cautiously because of our small sample size and the low statistical power of our study design.