Scholar in Residence in the Department of Psychiatry at the Johns Hopkins University School of Medicine
Con to the question "Is Sexual Orientation Determined at Birth?"
"While some people are under the impression that sexual orientation is an innate, fixed, and biological trait of human beings — that, whether heterosexual, homosexual, or bisexual, we are ‘born that way’ — there is insufficient scientific evidence to support that claim. In fact, the concept of sexual orientation itself is highly ambiguous; it can refer to a set of behaviors, to feelings of attraction, or to a sense of identity. Epidemiological studies show a rather modest association between genetic factors and sexual attractions or behaviors, but do not provide significant evidence pointing to particular genes. There is also evidence for other hypothesized biological causes of homosexual behaviors, attractions, or identity — such as the influence of hormones on prenatal development — but that evidence, too, is limited. Studies of the brains of homosexuals and heterosexuals have found some differences, but have not demonstrated that these differences are inborn rather than the result of environmental factors that influenced both psychological and neurobiological traits. One environmental factor that appears to be correlated with non-heterosexuality is childhood sexual abuse victimization, which may also contribute to the higher rates of poor mental health outcomes among non-heterosexual subpopulations, compared to the general population. Overall, the evidence suggests some measure of fluidity in patterns of sexual attraction and behavior — contrary to the ‘born that way’ notion that oversimplifies the vast complexity of human sexuality."
Cowritten with Paul R. McHugh, "Sexuality and Gender: Findings from the Biological, Psychological, and Social Science," The New Atlantis, Fall 2016