Last updated on: 2/5/2009 | Author:

William M. Byne, MD, PhD Biography

Director of the Laboratory of Neuroanatomy and Morphometrics at Mount Sinai School of Medicine
Not Clearly Pro or Con to the question "Is Sexual Orientation Determined at Birth?"

“Recent studies postulate biologic factors as the primary basis for sexual orientation. However, there is no evidence at present to substantiate a biologic theory, just as there is no compelling evidence to support any singular psychosocial explanation.

While all behavior must have an ultimate biologic substrate, the appeal of current biologic explanations for sexual orientation may derive more from dissatisfaction with the present status of psychosocial explanations than from a substantiating body of experimental data. Critical review shows the evidence favoring a biologic theory to be lacking.

In an alternative model, temperamental and personality traits interact with the familial and social milieu as the individual’s sexuality emerges. Because such traits may be heritable or developmentally influenced by hormones, the model predicts an apparent nonzero heritability for homosexuality without requiring that either genes or hormones directly influence sexual orientation per se.”

“Human Sexual Orientation. The Biologic Theories Reappraised,” Archives of General Psychiatry, Mar. 1993

Involvement and Affiliations:
  • Director, Laboratory of Neuroanatomy and Morphometrics, Mount Sinai School of Medicine
  • Associate Professor, Psychiatry, Mount Sinai School of Medicine
  • Editorial Board, Journal of Homosexuality
  • Editorial Board, Journal of Gay & Lesbian Psychotherapy
  • Former Research Associate, Albert Einstein College of Medicine, Yeshiva University
  • Former Attending Psychiatrist, New York State Psychiatric Institute
  • Former Psychiatric Resident and Neuroscientist, Columbia University
  • Outstanding Resident Award, National Institute of Mental Health, 1991
  • MD, Albert Einstein College of Medicine, Yeshiva University, 1989
  • PhD, Neurosciences Training Program, University of Wisconsin-Madison, 1985
  • None found
Quoted in:
  1. Do Studies Conducted on Homosexuality in Twins Show a Genetic Basis of Sexual Orientation?
  2. Can Hormones Affect Sexual Orientation?
  3. Are There Physical Differences in the Brain Structure of Heterosexual and Homosexual People?
  4. Is There a Gay Gene?