Increased incidence of HLA antigen B35 in patients with chronic lymphocytic leukemia.

We and others have reported an increased incidence of chronic lymphocytic leukemia (CLL) among Ashkenazi (ASH) Jews of European origin. We performed HLA Class I typing on all 50 CLL patients seen by us and compared them with 3886 controls consisting of healthy blood donors from the New York Blood Center. Thirty of our CLL patients were ASH Jews, 17 of whom (57%) expressed the B35 antigen compared with 462 ASH controls (26%). Seven (39%) of the CLL Caucasian patients expressed the B35 antigen compared with 305 (14.5%) of the Caucasian controls. Combining the information from the ASH Jews and the Caucasians the difference is highly significant, (p = 0.0001). The summary odds ratio was 3.7. These results indicate an increased incidence of the antigen B35 amongst ASH and Caucasian patients with CLL.