Genetic marker association in schizophrenia: ABO, MN, Rhesus and Lewis blood groups.

One hundred and twelve Chinese male patients suffering from schizophrenia were investigated for the distribution of A1A2BO, MN, Rhesus (genotypes) and Lewis(a) blood groups. The same genetic markers were investigated in 114 Chinese male blood donors. Two more published series--one on the distribution of ABO blood groups and the other on Le(a) blood groups in healthy Chinese males were also used as additional control series. The relative frequencies on these blood groups were examined between the schizophrenics and the control series. There was no significant association of ABO, MN and Rhesus blood groups in schizophrenia. However, a significant association was observed with the Le(a) blood groups with an excess of Le(a) positives in schizophrenia (p less than 0.02).