Hairy cell leukemia in two siblings. A human leukocyte antigen-linked disease?

Shared haplotypes have been documented in three of the four previously reported families with familial hairy cell leukemia (HCL). Human leukocyte antigen (HLA) typing was done on a four-member sibship in which two siblings had hairy cell leukemia. The two affected siblings share the haplotype A2; Bw6, Bw62(15); Cw1; DR4, DRw53; DQw3. No one HLA antigen or haplotype is common among the five families reported at this time. These limited data suggest HCL is not associated with a specific HLA antigen. HLA typing of a larger collection of cases of familial HCL may help better define what role, if any, inheritance plays in the occurrence of this rare disorder among numerous first degree relatives.