Genetic markers for schizophrenic subgroups.

By the study of hereditary serum protein markers in psychotic patients and normal controls, a surplus of Gc 1-1 (p less than 0.01) and transferrin B variants (p less than 0.0027) has been established in schizophrenias. Affective psychoses are characterized by an excess of the haptoglobin (Hp) serum type 2-2 (p less than 0.001). These general statements have to be modified in regard to the clinical and psychopathological subdivision beyond the traditional classification into two major groups of endogenous mental disease. Using Leonhard's criteria, the prevalence of Gc 1-1 is restricted to the systematic schizophrenias reaching its highest value in hebephrenias, which are followed by paraphrenic and catatonic forms in this trait. In contrast to this, periodical catatonia and affective paraphrenia, classified as subgroups of the unsystematic schizophrenias, have Gc 1-1 frequencies like healthy controls. On the other hand, the Hp 2-2 value is not increased in the systematic schizophrenias, but it displays a relative overplus in the unsystematic forms. Concerning the Hp 2-2 and Gc 1-1 frequencies a certain similarity can be observed between affective paraphrenia and the paranoid psychoses with late onset, it they are characterized by a cyclic axis syndrome as described by the Vienna school. The cycloid psychoses are marked by an extreme surplus of Hp 2-2 (p less than 0.001) and an overweight of Gc 1-1 (p less than 0.05). Probably the Gc and Hp alleles play a role as risk factors or accidental effectors in the multifactorial genetic systems responsible for the biological background of psychoses. For both serum systems a selective interaction is discussed considering the vitamin D transport by the Gc proteins with the relation to neuronal consolidation and the possible influence of Hp 2-2 on transport and receptor functions.