Genetic studies in multiple myeloma. 1. Association with HLA-Cw5.

Human leukocyte antigens (HLA) were identified in 22 black Americans with multiple myeloma. No significant association was observed between antigens at either the A or the B locus. At the C locus, in contrast, HLA-Cw5 was more prevalent in the patient group, four of 22 having it, compared with the control group, in which two of 138 individuals possessed it. All four patients with HLA-Cw5 were males. Those results suggest that genetic factors, perhaps in conjunction with an environmental change, may be responsible for the recent increase in incidence in myeloma in black Americans, especially in males.