Recent progress in clonal hematopoiesis: expanding the concept

Area of Science:

• Hematology
• Genetics
• Immunology
• Gerontology

Background:

• Clonal hematopoiesis (CH) is an age-related phenomenon involving somatic mutations in hematopoietic stem cells.
• Initially linked to hematologic neoplasms, CH now connects to non-malignant diseases and increased all-cause mortality.
• Mutations in DNMT3A, TET2, and ASXL1 drive clonal expansion, impacting epigenetic regulation and immune signaling.

Purpose of the Study:

• To explore the natural history, genetic basis, and inflammatory manifestations of CH.
• To understand CH's role as a biomarker and potential therapeutic target in aging populations.
• To highlight CH's implications beyond hematologic malignancies, as exemplified by VEXAS syndrome.

Main Methods:

• Review of longitudinal studies on clonal growth dynamics.
• Analysis of germline variant influence on somatic selection.
• Examination of genetic underpinnings of CH, including frequent mutations (DNMT3A, TET2, ASXL1) and specific syndromes (VEXAS).

Main Results:

• CH is a significant contributor to increased all-cause mortality, especially via cardiovascular and inflammatory diseases.
• Somatic mutations in CH alter epigenetic regulation and immune signaling, promoting clonal expansion.
• Germline variants play a role in somatic selection and clonal expansion dynamics.

Conclusions:

• Clonal hematopoiesis represents an intermediate biological state with broad clinical implications.
• CH serves as both a critical biomarker and a potential therapeutic target in aging.
• Understanding CH is crucial for managing age-related diseases and mortality.