Nonlinkage of bipolar illness to tyrosine hydroxylase, tyrosinase, and D2 and D4 dopamine receptor genes on chromosome 11

Objective: Previous linkage and allelic association studies using DNA polymorphisms, cosegregation of cytogenetic abnormalities with psychiatric illness, and assignment of genes involved in neurotransmitter metabolism suggested that chromosome 11 may harbor a gene predisposing to bipolar illness. The authors examined linkage in the families of 14 probands with bipolar illness, with the candidate genes tyrosine hydroxylase (TH), D 4 dopamine receptor (DRD4) at 11p15, tyrosinase (TYR) at 11q14-q21, and D 2 dopamine receptor (DRD2) at 11q22-q23, as well as with the c-Harvey-ras oncogene (HRAS) and insulin gene (INS), both located at 11p15, a region that previously showed linkage to bipolar illness