Clonal hematopoiesis (CH) is defined as the age-associated expansion of hematopoietic stem and progenitor cells harboring somatic mutations, most frequently in epigenetic regulators such as DNMT3A, TET2, and ASXL1. Although CH was initially recognized as a precursor to hematological malignancies, accumulating evidence has led to its broad recognition as a relevant factor in various age-related nonmalignant diseases, particularly those with inflammatory components, such as cardiovascular disease, autoimmune disorders, and solid tumors. The gene discussed is ASXL1; the disease is autoimmune disease.