Heterochromatic variants and their association with neoplasias. I. Chronic and acute leukemia.

C-banding studies of the heteromorphism of chromosomes #1, #9, and #16 were performed in 120 leukemic patients: 56 with chronic myelocytic leukemia (CML), 45 with acute lymphoblastic leukemia (ALL), and 19 with acute nonlymphoblastic leukemia (ANLL). No differences were found among patients and controls with regard to sex. Our data showed a significant increase of polymorphism in chromosome #1 in the three neoplastic groups; the heterochromatic variant preferentially involved 1qh-, whereas there were no significant differences in heteromorphism in chromosomes #9 and #16.