RT-PCR analysis expression of P55, IDS, and G6PD genes in patients with monoclonal hematopoiesis. RNA of heterozygous patients was submitted to RT-PCR. Amplified products were digested with Hha I, HpaII and Pvu I, respectively, and analyzed by gel electrophoresis and ethidium bromide staining. Three to 24 correspond to the patient numbers in Table 4. U, undigested PCR products; P, platelets; T, T lymphocytes. Arrows indicate the size of the fragments in base pairs.