Hepatitis B virus, sex ratio and the H-Y antigen.

The hypothesis that Hepatitis B surface Antigen (HBsAg) is cross-reactive with the male-specific H-Y antigen has been tested. In none of three separate experiments using selected anti-HBs sera, or in a fourth experiment using anti-H-Y sera, could any evidence for cross-reactivity be detected. Our results are therefore not compatible with the idea that altered sex-ratios observed among offspring of parents infected with Hepatitis B virus are related to cross-reactivity between HBsAg and a male-associated antigen.