Prior to 1990 there was a paucity of studies directed at psychiatric genetics and in fact there was only one study by Egeland et al. . whereby an analysis of the segregation of restriction fragment length polymorphisms (RFLP) in an Old Order Amish population (pedigree) localized a dominant gene linked to a strong predisposition to manic depressive disease to chromosome 11 possibly tyrosine hydroxylase.
This finding was retracted in 1989 by Kelsoe et al. . Following these very early studies Blum and Noble and their respective groups reported on the first ever confirmed association of the dopamine D2 receptor gene (DRD2) and severe alcoholism . While this sparked some controversy  it was confirmed  and remains the most widely studied gene in psychiatric genetics and lead to the development of an entire field of medicine (PubMed 8/8/14- 14,661) –known as Psychiatric Genetics.
Published on: Oct 17, 2014 Pages: 11-14
Prof. Pierre Guertin
Laval University, Canada
International Journal of Pharmaceutical Sciences and Developmental Research
University of Athens, Greece
Journal of Novel Physiotherapy and Physical Rehabilitation
Domenico Antonio Restivo
Nuovo Garibaldi Hospital, Italy
Journal of Neurology, Neurological Science and Disorders
National Center for Toxicological Research (NCTR)/FDA, USA
Global Journal of Anesthesiology
Jose Manuel Ramia-Angel
Guadalajara University Hospital , Spain
Journal of Surgery and Surgical Research