Somatic mutations (also known as acquired mutations) are emerging as common, age-related processes that occur in all cells throughout the body. Somatic mutations are canonically linked to malignant processes but over the past decade have been increasingly causally connected to benign diseases including rheumatic conditions. Here we outline the contribution of somatic mutations to complex and monogenic immunological diseases with a detailed review of unique aspects associated with such causes. Somatic mutations can cause early- or late-onset rheumatic monogenic diseases but also contribute to the pathogenesis of complex inflammatory and immune-mediated diseases, affect disease progression and define new clinical subtypes. Although even variants with a low variant allele fraction can be pathogenic, clonal dynamics could lead to changes over time in the proportion of mutant cells, with possible phenotypic consequences for the individual. Thus, somatic mutagenesis and clonal expansion have relevant implications in genetic testing and counselling. On the basis of both increased recognition of somatic diseases in clinical practice and improved technical and bioinformatic processes, we hypothesize that there will be an ever-expanding list of somatic mutations in various genes leading to inflammatory conditions, particularly in late-onset disease.

体细胞突变（也称为获得性突变）正在成为常见的、与年龄相关的过程，发生在全身的所有细胞中。体细胞突变与恶性过程密切相关，但在过去十年中，与包括风湿性疾病在内的良性疾病的因果关系越来越大。在这里，我们概述了体细胞突变对复杂和单基因免疫疾病的贡献，并详细回顾了与此类原因相关的独特方面。体细胞突变可导致早发性或晚发性风湿性单基因疾病，但也有助于复杂炎症和免疫介导疾病的发病机制，影响疾病进展并定义新的临床亚型。尽管即使是变异等位基因分数较低的变异也可能具有致病性，但克隆动力学可能导致突变细胞比例随时间变化，从而可能对个体产生表型后果。因此，体细胞诱变和克隆扩增在基因检测和咨询中具有相关意义。基于临床实践中对体细胞疾病的认识增加以及技术和生物信息学过程的改进，我们假设导致炎症状况的各种基因中的体细胞突变列表将不断扩大，尤其是在晚发性疾病中。