Blanchard’s main research interests are phallometric diagnosis, gender identity disorders, sexual orientation, and paraphilias. His research in the field of sexual orientation has shown that older brothers increase the odds of homosexuality in later-born males. This phenomenon has been called the fraternal birth order effect. He has advanced the hypothesis that the phenomenon reflects the progressive immunization of some mothers to male-specific antigens by each succeeding male fetus, and the concomitantly increasing effects of anti-male antibodies on the sexual differentiation of the brain in each succeeding male fetus. Blanchard ’s current research, in collaboration with Anthony F. Bogaert and his colleagues at Brock University, is a serological study investigating the hypothesis that the relevant male-specific antigen might be PCDH11Y (which Blanchard first suggested in 2002) or NLGN4Y (which Blanchard first suggested in 2004).
Ray Blanchard (born October 9, 1945 in Hammonton, NJ) was Head of Clinical Sexology Services in the Law and Mental Health Program at the Centre for Addiction and Mental Health (CAMH) in Toronto, Ontario from 1995 to 2010. He is currently a status-only Full Professor of Psychiatry at the University of Toronto. He received his A.B. in psychology from the University of Pennsylvania in 1967 and his Ph.D. from the University of Illinois in 1973. He then took up a Killam Postdoctoral Fellowship awarded by Dalhousie University in Halifax, Nova Scotia, where he remained until 1976, investigating learning processes in animals. In 1976 he accepted a position as a clinical psychologist at the Ontario Correctional Institute in Brampton, Ontario.
Blanchard joined the Gender Identity Clinic at the Clarke Institute of Psychiatry (now part of the CAMH) in 1980. Much of his research in the next 15 years concerned transsexualism and milder forms of gender identity disorders. In 1995, he was appointed Head of the newly created Clinical Sexology Services at the CAMH. This unit comprised the Gender Identity Clinic and the Kurt Freund Laboratory. In 2004, he served as President of the International Academy of Sex Research. He was a member of the Sexual and Gender Identity Disorders Work Group for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. In 2010, he received a Significant Achievement Award from the Association for the Treatment of Sexual Abusers.