Genetic polymorphism of ABO and Rh system in relation to bronchial asthma: preliminary report.

115 asthmatic children and 1001 healthy voluntary blood donors were studied in order to determine the distribution of blood groups among them. Gene frequencies were also calculated in asthmatic patients and controls. No difference was noted between Rh system in both groups; but the ABO system showed an excess of blood group A among asthmatic patients. Gene frequency of A (p) and gene frequency of O (r) was quite different too for asthmatics and controls. No difference was noted in blood groups B and AB; nor in the gene frequency of B(q). The difference in the distribution of blood group A and O between control and asthmatic groups was found to be highly significant (P less than 0.02) with the chi-square test.