A Study of Association and Linkage of ABO Blood Types and Primary Affective Disorder

¹ Department of Psychiatry, Washington University School of Medicine, 4940 Audubon Avenue, St. Louis, Missouri 63110

The frequency of ABO blood types of a group of 65 patients diagnosed as having primary affective disorder was compared with a selected group of 65 controls. The controls were members of the same families as the patients. There was no difference in distribution of blood types between primary affective disorder group as a whole and the control group. However, B type blood occurred with somewhat greater frequency (p<.05) in the primary affective disorder patients who had a positive family history of affective disorder in a first degree relative. Because this conflicts with previous findings in the literature, it is concluded that at present there is insufficient evidence to assume association between ABO blood types and affective illnesses.

Using sib-pair method, an attempt was made to demonstrate linkage between the ABO blood system and affective disorder. Numerous subgroups were compared, and it is concluded that none of them show evidence for linkage. Nevertheless, the method may be used with any available genetic markers to detect possible linkage in psychiatric illnesses in which there is some evidence of a genetic factor. Linkage between primary affective disorder or a type of primary affective disorder and a genetic marker would enable researchers to obtain more homogeneous groups and to predict more specifically which member among a family would be likely to get the illness.