RecruitingCHIP/CCUS Natural History ProtocolBackground: Clonal Hematopoiesis of Indeterminate Potential (CHIP) is a change in a person s DNA that can increase a person s risk of developing blood cancers or cardiovascular disease. CHIP occurs mostly occurs in older people. Clonal cytopenia of undetermined significance (CCUS) occurs when one or more blood cell types is lower than it should be and is associated with a change in their DNA. Researchers want to learn more about how CHIP and CCUS progress. Objective: To examine the natural history of people in a study of CHIP and CCUS to (1) verify the association of myeloid somatic mutations with atherosclerosis and blood cancers, and (2) find new potential clinical associations. Eligibility: Adults 18 and older with CHIP with a somatic pathogenic variant associated with blood cancers. Adults with CCUS are also needed. Design: Potential participants will be screened with gene testing. For this, they will give a blood sample. They will also be enrolled in NHLBI screening protocol #97-H-0041. Those who pass this screening will visit the NIH Clinical Center for more screening tests. For this, they will give a blood sample. They will have a physical exam. They will give their medical history. They may give a urine sample. Those with CCUS will have bone marrow taken. Eligible participants will give blood and urine samples. Their heart activity will be monitored and tested. The arteries in their neck will be assessed using ultrasound. They will have liver and heart scans. They will have a bone mineral density scan. They will have lung function tests. They will have the inside of their cheek swabbed or have a skin punch biopsy. They will have the option to have advanced scans done of their heart and full body but this is not required. Participants will have yearly follow-up visits for 10 years. They will repeat the above procedures every 1-3 years depending on the procedure.