An association between cutaneous sensitivity to histamine and HLA phenotype

Four hundred and twenty randomly chosen subjects from a normal population were HLA typed and tested for cutaneous sensitivity to histamine by prick testing with 5 concentrations of histamine (10(-3), 10(-2), 10(-1), 1, 10 mg X ml-1). Positive responses to 10(-1) mg X ml-1 histamine occurred in 41% of the subjects, and particularly those with HLA-B7 (55%) (p less than 0.005). It is concluded that genes within the major histocompatibility complex influence cutaneous responses to histamine.