No evidence for a susceptibility locus predisposing to manic depression in the region of the dopamine (D2) receptor gene.

Recent reports of cytogenetic abnormalities linked to psychiatric illness and the localisations of the genes for the dopamine (D2) receptor and tyrosinase on the long arm of chromosome 11 have suggested that susceptibility loci for schizophrenia and manic depression might be situated in this region. We could find no evidence for linkage in five Icelandic pedigrees between manic depression and markers in this region, and we have excluded candidate genes coding for the D2 receptor and tyrosinase. We conclude that mutations at loci in this region are not a common cause of manic depression in the population studied.