Schizophrenia: Dopamine D1 receptor sequence is normal, but has DNA polymorphisms

Abstract

Genes that regulate dopamine (DA) receptors may underlie the overactive DA system in schizophrenia. Since it is known that there is an abnormally reduced or Ibsent regulation of the DA D2 receptor by the DA D1 m:eptor in the postmortem schizophrenia brain, the human DA D1 receptor gene was sequenced from genomic deoxyribonucleic acid (DNA) of seven schizophrenic individuals. The tissues from two schizophrenics had previously been found to have a reduced link between DA D1 and D2 receptors. The D1 receptor genes were amplified by the polymerase chain reaction, subcloned, and sequenced. Although three DNA polymorphisms were found, the deduced amino acid sequence of the DA D1 receptor was normal in these tissues. © 1993 American College of Neuropsychopharmacology.