Significant miR-145-a genotypes to serve as asthma predictors

Abstract Background: Asthma is a chronic airway inflammation disease and the diagnosis and treatment strategies remain difficult. The study and application of miRNAs have rapidly become one of the hot spots of translational medical sciences. There is no study confirming the contribution of the genotypes of miR-145 to asthma. We hypothesized the genotypes of miR-145 may influence the risk of asthma and aimed to test this hypothesis. Methods: In 198 asthma patients and 453 healthy controls, the genotypes of miR-145 rs4705342 and rs4705343 were determined, and the correlation of miR-145 genotypes with asthma severity were evaluated.Results: The distribution of miR-145 rs4705342 genotypes between asthma patients and non-asthmatic control groups were significantly different (p=0.0187). In detail, the variant CC genotypes were of lower proportions in asthma patients than in controls (OR=0.41, 95%CI=0.21-0.79, p=0.0102). The allele frequency analysis also showed a significantly differential distribution between the two groups (OR=0.69, 95%CI=0.53-0.90, p=0.0070). As for rs4705343, there was no such differential distribution. In addition, miR-145 rs4705342 variant genotypes were correlated with the symptom severity (p=3×10-5). Further, from the genotype-phenotype observation, there was a trend that C allele carriers prone to have a lower miR-145 expression level in their serum (p=0.0001). Conclusions: Our data provide evidence for miR-145 to serve as a novel biomarker for asthma risk prediction and early detection.