THIS week, we will go back to reviewing the evidence so far available on the contention that gender has a biological basis. For those who are late in following this discussion, gender is widely recognized by psychologists and sociologists as a personal choice, may it be based on sex (biological) identity or not.
However, certain sectors in the LGBT (lesbian, gay, bisexual, transgender) community have started pushing the argument that such gender identity is “in fact,” biological evidence.
One of the more comprehensive reviews of literature on this discussion was found in the study that Aruna Saraswat, Jamie Weinand and Joshua Safer reported to Endocrine Practice journal in 2015.
Last October, we reviewed the 2008 Garcia-Falgueras and Swaab study, which referred to the interstitial nucleus of the anterior hypothalamus 3 (INAH 3) as the potential basis for gender identity biologically.
This week, we proceed to the 2009 Luders et al. study, which tried to analyze the gender dichotomy using magnetic resonance imaging (MRI) on living male-to-female (MTF) transgender individuals before their use of extraneous female hormone treatment. The 24 volunteers had been found to have cerebral patterns similar to straight males (control group). The test group, however, also showed larger volume of more “feminized” gray matter at the right putamen. The putamen controls the motor functions or skills, from learning motor tasks to specific movement sequences and amplitudes.
Although Saraswat, Weinand and Safer interpreted this as evidence of feminization, the MRI patterns tended to disagree. These inconsistent findings leave us many questions in mind: Were the supposed differences in the motor skills of the MTF subjects a consequence of the “more feminized” right putamen? Or, is the “more feminized” right putamen a consequence of the supposed differences in the MTF motor skills compared with the male control? One thing more, were there significant differences in the motor skills of the MFT group and the male control group? The study seemed to have not emphasized that. Moreover, which method of analysis may be considered more valid in determining gender dichotomy? Is it the overall MRI patterns or the right putamen patterns?
Thus, the 2009 Luders et al. study, although providing inconclusive “hints,” cannot support with definiteness, that the MTF gender identity has biological basis.
Thomas Carlyle was quoted writing: “Conclusive facts are inseparable from inconclusive except by a head that already understands and knows.”