Color blindness linkage to bipolar manic-depressive illness. New evidence

Linkage between protanopia and deuteranopia and bipolar manic-depressive illness is demonstrated in a sample of eight informative families ascertained in Brussels. Genetic heterogeneity of bipolar affective disorders is also shown in the present study. These results add new evidence to the hypothesis of X-linked dominant genetic transmission of affective liability in a subgroup of patients with bipolar affective disorders.