EXCESS OF HLA-A2 AND HOMOZYGOUS HLA-A2 IN PATIENTS WITH APLASTIC-ANEMIA AND FANCONIS ANEMIA

Abstract

In 68 idiopathic aplastic anemia patients (65 HLA genotypes), HLA-A2 is slightly increased (P corrected < 0.03) leading to a relative risk of 2.30. A slight excess of homozygotes for HLA-A was observed (22.2 vs. 14.09%), involving mostly the A2 antigen. In the siblings the patients were more frequently homozygote A2 than by chance (P < 0.005). The same trends are observed in Fanconi''s anemia, out of 18 patients, 7 are HLA-A homozygote (of whom 4 are A2). The hypothesis of the existence of 1 or several recessive genes involved in hematopoiesis situated close to HLA-A is advanced.