To test the hypothesis that liver function is different in populations with inherited susceptibility to persistent Australia antigen (hepatitis B surface antigen [HBsAg]), Sardinians living in Turin, Italy, were compared with their native Turinese neighbors. The study was controlled for age, sex, place of birth, and presence or absence of persistent HBsAg. Slight differences in liver function were found in the Sardinians compared with the Turinese. Their values were in the direction of abnormality. Sardinians also had considerably higher serum γ-globulin levels than the Turinese. The levels of α2-globulin by electrophoresis correlated with the presence of HBsAg.