MicroRNAs (miRNAs) are small non-coding RNAs that posttranscriptionally regulate the expression of most genes. They are involved in regulating many physiological processes, and aberrations in the levels of different miRNAs play an important role in the development of many diseases, including autoimmune diseases, neuropsychiatric diseases, and cancers. Although miRNAs are being intensively studied and levels of many miRNAs are either specifically increased or decreased in particular diseases, very little is known about the genetic variations of miRNA genes and their impact on the functioning of miRNA genes and human diseases. To shed more light on the potential effects of genetic variants in miRNA genes, we review here representative examples of SNPs, mutations linked to Mendelian diseases, and cancer somatic mutations located in miRNA genes and discuss their potential effects on the expression of miRNA genes, i.e., the structure and processing of miRNA precursors, the levels of generated miRNAs, miRNA target recognition/silencing, and impact on human diseases.

微小 RNA (miRNA) 是小的非编码 RNA，可在转录后调节大多数基因的表达。它们参与调节许多生理过程，不同 miRNA 水平的异常在许多疾病的发展中起着重要作用，包括自身免疫性疾病、神经精神疾病和癌症。尽管正在对 miRNA 进行深入研究，并且许多 miRNA 的水平在特定疾病中特异性升高或降低，但人们对 miRNA 基因的遗传变异及其对 miRNA 基因功能和人类疾病的影响知之甚少。为了更多地了解 miRNA 基因中遗传变异的潜在影响，我们在此回顾了 SNP 的代表性例子，与孟德尔疾病相关的突变，