An editorial published in the January 2010 edition of the American Journal of Psychiatry:
By John H. Gilmore, M.D.
Understanding what causes schizophrenia is becoming harder and harder. We know that schizophrenia has genetic causes, since the most significant risk factor is having a first-degree relative with schizophrenia. However, most people with schizophrenia do not have an affected relative, and while the overall genetic contribution to schizophrenia may be large, the contribution of specific genes is very small. Candidate gene studies and more recent genome-wide association studies have had inconsistent results and indicate, at best, individual genes increase risk by less than 2 times—from an average population rate of 1 in 100 to 1.5 in 100. Pre- and perinatal complications and environmental exposures appear to have somewhat stronger effects than individual genes, as prenatal exposure to infection or hypoxia increases risk of schizophrenia from 1 in 100 to 2–4 in 100 (1). Schizophrenia is likely the result of an interaction between genetic risk and environmental exposures, and recent studies have attempted to describe that interaction.
To read the entire editorial, please click here.
I thank Dr. David Whitehorn for bringing this article to my attention.