Apparently healthy HBsAg carriers: sex-dependent difference in ABO blood group distribution, subtype ratio and antigen titer

The results obtained by subtyping and titration of 872 HBsAg from apparently healthy carriers were grouped according to blood group and sex. The incidence of blood group AB is higher among healthy HBsAg carriers than in the unselected population. There are large variations as regards the ay : ad ratio (overall mean value : 4.74) : minimal ay : ad values occur in the AB blood group, both in men (4.00) and in women (1.33), as compared with the mean values of 5.07 and 2.95 recorded in men and women, respectively. Titer analysis shows a cluster of higher titers in women. The involvement of immunogenetic mechanisms in asymptomatic HBsAg carriage is suggested.