ABSTRACT
Fifty-seven members from ten families in which one parent and at least one child have asthma were studied with dilutional skin tests and RAST to grass pollens after determination of HLA haplotypes. We found no direct evidence for linkage of a hypothetical asthma locus with HLA or for a significant association of asthma with HLA haplotypes. Linkage between the HLA loci and a gene or genes which allow for the expression of clinical asthma could neither be proven nor disproven due to the small sample size. All of the asthmatic children had positive dilutional skin tests and RAST, suggesting that atopic asthma may be genetically controlled by the HLA chromosome (chromosome 6). Nonetheless, determination of the histocompatibility antigens can increase the value of predictive risk analysis for asthma. Such a determination may be important in the early identification of a child born to a family with atopic asthma.