Population and family studies to demonstrate Ir genes: HLA haplotype in atopic allergy.

47 normal healthy controls and 45 atopic individuals together with five families with allergic diathesis and sensitive to mite antigen were typed for 13 HLA antigens. In general population, HLA-A1 and HLA-A8 were found to be higher than in normal controls. But the difference was significant at a level of p 0.05 after correction was made for the number of HLA antigens used. In one family, an HLA-A1 -B8 haplotype seems to be linked to the manifestation of atopic disease. The pattern of association of an HLA-A9 -B7 haplotype with the disease process in another family indicates that multiple genes may be involved in the manifestation of a variety of allergic disorders. Although more than one HLA haplotype of HLA-associated Ir gene for one antigen have been postulated, we still do not have enough evidence to suggest linkage between HLA haplotypes and atopic allergy. Further studies utilizing mixed lymphocyte culture and carefully matched control with a large number of subjects and more families are in progress to study the genetic basis of allergic diseases.