HL-A3 and HL-A7 in pernicious anaemia and autoimmune atrophic gastritis.

Increased frequencies of HL-A7 and the HL-A3,7 haplotype have been demonstrated in pernicious anaemia. There was no significant increase in any HL-A specificity in autoimmune atrophic gastritis. In the whole series of patients with either pernicious anaemia or atrophic gastritis there was a significant increase in the frequency of HL-A3. No association has been found between any HL-A specificity and an increased incidence of either serum gastric parietal cell or intrinsic factor antibody compared with the overall incidence in pernicious anaemia, atrophic gastritis or in the whole series.