The dominance of the IGHG2*n allele from the IGHG*bfn haplotype (=B1-cells) has been shown in repeated investigations, namely in patients with asthma and allergy with increased serum levels of IgE > 600 ku/l and more often so in those with IgE > 1,000 ku/l or IgG4>1 g/l, in childhood asthma patients with mean level of IgE = 1,762 ku/l and in allergen exposed individuals developing laboratory animal allergy.