[Distribution of blood groups, salivary blood group substances, and natural antibodies in a sample of MZ twins (author's transl)].

The distribution of A1A2BO, MN, and Rh-Hr blood groups, of salivary ABH substances, and of natural antibodies, was assessed in a sample of 47 MZ twin pairs. The resulting distribution provides indications as to the level of genetic control over the quantitative expression of these traits.