HLA associations in Italian and non-Italian Caucasoid aplastic anaemia patients.

A reassessment of HLA-A and B antigen associations in patients with severe aplastic anaemia confirmed the significantly elevated frequency of HLA-A2 in Caucasoid patients reported by Albert et al. (1976). In addition, a highly significant increase in the frequency of HLA-B14 in Italian patients was observed in an initial sample of 25 patients and confirmed in a second sample of 16 patients. This latter finding was cancelled out when the Italian Caucasoid patients were pooled with the non-Italian Caucasoid patients. These results suggest that the classification of populations as "Caucasoids", without examining their ethnic origins, may introduce a serious confounding error into HLA and disease studies.