CHIP is the acronym for "Clonal Hematopoiesis of Indeterminate Potential" and means that certain blood stem cells have mutations. This allows them to multiply easily and form a clone population in the blood. CHIP mutations are somatic (non-inherited) mutations that occur in genes that are also frequently altered in hematologic neoplasias, e.g.:
CHIP mutations are often found by chance in older people. They do not cause any symptoms or disease - but can slightly increase the risk of later blood diseases (e.g. leukemia).
Why are CHIP mutations important in oncology? In ctDNA analyses (blood tests for tumor diagnostics), CHIP mutations can be mistaken for tumor mutations because both occur in the blood. This can lead to false-positive results.