Peripheral blood smears from leukemia patients exhibit bizarre hyperlobated nuclei known as “clover leaf” or “flower cells.” For immunophenotype, the origin of the malignant cell in ATLL is an HTLV-I-infected memory CD4+ T lymphocyte which expresses CD2, CD3, CD4, and CD25 in most cases. The gene discussed is CD4; the disease is leukemia.