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Gender Self-Identity Among Males: A Case for Biology

Anna Dela Cruz's picture

      I remember freshman year when my roommate and I had a conversation about gender and sexuality. To her there were three distinctions: sex deals with anatomy (genitalia in particular), gender is a social construction dictated by not only culture but also by how one identifies himself or herself based on personality traits, and sexuality deals with who one is physically and romantically attracted to. To her, gender and sex do not necessarily equal each other. At the time of this long ago conversation, I was in awe. Contrary to what my roommate believed, I had thought that gender and sex were interchangeable words of the same meaning—that behavior and biology are closely linked. In my Gender and Technology class, I have come across the idea that gender is a social construction and that the anatomy we are born with, especially our sex organs, has nothing to do with behaviors associated with our self-identified gender. But what if one’s biology has a major impact on one’s own gender identity? I argue that from a biological standpoint, sex chromosomes and genitalia are not the only influences over gender identity. Case studies have strongly suggested that prenatal and postnatal hormonal influences do have a significant impact over gender identity.

     More than forty years ago, gender was redefined as a social construction as well as malleable. In the 1960’s a psychology professor at Johns Hopkins University named John Money fervently believed that babies were born gender neutral (1). To him, one was not born male or female but rather became one or the other through life experiences and behavioral conditioning. Operating under this notion of gender neutrality, he also believed that a perfectly healthy boy born with no sex chromosomal abnormalities can be raised as a girl and eventually grow into a stable woman and vice versa.

     So when the Reimer family, dealing with the heartbreaking predicament of an infant son’s complete loss of his penis after a botched circumcision, came to Money in 1966 for help, the psychology professor was confident in suggesting the baby boy be raised a girl. Since the baby boy of concern, Bruce, had an uncircumcised identical twin brother, Brian, this family’s dilemma presented the perfect opportunity for a social experiment in which Bruce offered the experimental condition by being raised as a girl, and Brian offered the control condition by being raised a boy (1). This particular social experiment formally known as the John/Joan Case, also known as the Bruce/Brenda Case or the David/Brenda Case, would later become infamous in its total failure and Money’s unethical social experiment.  

     In what seems an ongoing debate on nature versus nurture, the adult Bruce Reimer attests to the determinacy of nature. In John Money’s observations of the Reimer brothers throughout their development, the psychologist wrote that the Bruce, or rather, Brenda was assimilating well into the female gender. He was wrong. Brenda was not happy as a girl, and in fact, was very masculine (1). As a result of her masculine physical attributes, her peers called her “Cave Woman” (1). When her mother put her in a dress for the first time, Brenda tried to rip it off (1). While being called a “Cave Woman” and trying to rip off a dress do not automatically constitute male gender identity, the fact that Brenda decided to live her adult life as David (after the Biblical figure), a straight man, does attest to his male gender identity. His life is an example of a man following his biological destiny. He was born a healthy normal male and despite being raised as female, he ultimately reverted to the gender identity as determined by his biology.

      In another case attesting to the power of biology concerns Liana and Juanita Barbachano, a pair of originally female identical twins until Juan received a sex change operation turning him into Juan. Juan reported that despite being born and raised as a girl, he had always felt male (2,3). Liana, however, did not experience this gender dysphoria growing up. One explanation for this dramatic difference between identical twins is based on differences in prenatal hormonal environments the twin were exposed to. Just before their birth, their mother was involved in a near-fatal car accident (3). Dr. Nancy Segal of California State University at Fullerton theorized that this accident could have triggered their mother to release adrenaline that somehow affected Juan but not Liana (3).

     The idea of a hormonal change to prenatal environment having an impact over the eventual gender self-identity of the baby is plausible. During the time John Money championed the notion of gender neutrality, Dr. Milton Diamond, a biologist at the University of Hawaii conducted a study on rat models that strongly suggested otherwise (1). Diamond reasoned that since animals behave according to their biology (i.e. following their instincts) and that humans are generally regarded as animals, humans therefore behave according to their instincts as well (1). His rat models study increased the level of testosterone in the hormonal environments of female rats in uteri. Upon reaching maturity, these sex-chromosome normal female rats mated in a manner consistent with that of male rats (1). In other words, these experimental female rats behaved as if they were male rats. In a related rat model study by Dr. Roger Gorski et al investigated structural brain differences between males and females. After analyzing slice after slice of rat brain tissue, the team found that the size of the hypothalamus (responsible for hormone release) in males was twice as large as the size found in females (1). Female rats exposed to extra testosterone levels in uteri developed hypothalamuses the size of that found in males (1). In a more applicable study, Dr. Dick Swab of the Netherlands Institute also investigated the size differences of the hypothalamus between males and females (1). Again, human males were found to have hypothalamuses twice the of that found in females (1). With this discovery, Swab believes that transsexuals such as Juan Barbachano have the brains of the other sex such that transgender men (persons who were born physically female and transition to male) have the hypothalamus size of that found in males, and therefore they behave and identity as male (1).

      The cases presented by both David Reimer and Juan Barbachano are intriguing. In Reimer’s case he was born a sex-chromosome normal boy who was raised as a girl, but then chose to live the rest of his life as a man having experienced gender dysphoria for most of his childhood and adolescent life. In Barbachano’s case he was born a sex-chromosome normal female, but a dramatic hormonal change to his prenatal environment may have been responsible for his gender dysphoria. I believe that both Reimer and Barbachano have hypothalamuses the size of a male’s and therefore both behaved like men. In Reimer’s case the size of his hypothalamus was determined by his genetic makeup having been born a normal male. In Barbachano’s case, the size of his hypothalamus was likely due to a hormonal change to his prenatal environment rather than genetic makeup. Nevertheless both cases present evidence supporting biological influence over gender identity. I am not saying that gender is not influenced by social stimuli, however, that fact that biology, in terms of hormones and hypothalamus size, has an affect on gender identity rejects the idea that gender is a social construction. Reimer and Barbachano were both reared as female and yet both chose to live as male.    

1)    Sex: Unkown. NOVA. PBS. WITF, Harrisburg. 30 October 2001
2)    Goldberg, Alan B. Identical Twins Become Brother and Sister: Female Twins Become Sister and Brother After Sex-Change Surgery. ABCNews website,; accessed 17 April 2009
3)    Transgender Twin Offers New Insight: Identical Female Twins Become Sister and Brother. ABCNews website,; accessed 17 April 2009


Lourdes Avainea Dressler's picture

gender dyshoria

been this way since 5. multiple personalities 5 female 4-men and sometimes I cant keep track!! I am comuter savvy so the sites I go to the next just is amazing I would like to donate my brain for reseach fo said condition thanx lourdes