Association of familial leukemia with HLA Cw3: is it real?

A kindred with familial leukemia is described in which three members are affected by leukemia in three consecutive generations. One of these members had Philadelphia positive chronic myeloid leukemia (CML) and other two had precursor B acute lymphoblasticleukemia (ALL)--Philadelphia negative. All three of them shared a common haplotype A2, B55, Cw3. In addition, another member sharing same haplotype developed metastatic breast cancer. Phenomenon of anticipation is demonstrated in the affected family members. Possible causes of genetic susceptibility to leukemia especially the association of Cw3 with familial leukemia are discussed.