Immunogenetic factors in thalassemia and hepatitis B infection. A multicentre study.

Geographical variations in the prevalence of hepatitis B infection were found in association with an increased opportunity of exposure to this virus in patients with homozygous beta-thalassemia in Cyprus, Greece, Sardinia and the United Kingdom. No association was found between the Gm phenotype of the individuals investigated and susceptibility to hepatitis B virus using HBsAg as a marker, or the ability to make antibody to it. Variation in the distribution of Gm haplotypes does not appear to be a feasible explanation for variation in anti-HBs and HBsAg frequencies in a series of highly transfused populations.