Why are girls born as girls, and boys as boys? What about an individual who is biologically female but feels or sees oneself as male, or the other way around?
Dr. Qazi Rahman who is a lead investigator into LGBT mental health at King’s College London revealed that science still can’t give a complete answer to those questions.
‘This is the key question at the moment,’ the scientist told The Guardian. ‘We know much more about how nature shapes sexual orientation, and my view of the science is that nurture does very little, if any, shaping of sexual orientation. We know next to nothing about how people come to feel transgender.’
Last year, a group of scientists had reportedly come up with a genetic test that’s able to predict for homosexuality up to a 67% accuracy rate.
One of the lead scientists, Tuck C. Ngun, who is a gay man, decided to withdraw from the research project due to the potential moral implications he foresaw.
At the moment no ‘transgender’ gene has been found. But would future trans focused research go the same way as Ngun’s?
Previous studies show that trans people have brains that are not wholly male or female, but with specific areas and systems that are masculinised or feminised.
It is unknown if these unique differences are short-term or permanent, or whether the brain would undergo changes following hormone therapy which many trans individuals take up.
In the womb, an embryo begins its journey of becoming male or female at around 6-8 weeks.
A gene called SRY on the Y chromosome would start encoding a protein called testis-determining factor (TDF), which initiates male sex determination.
Subsequently, the male sex hormone, testosterone, is produced in the embryo’s body, kickstarting masculinisation in its anatomy and physiology. Without testosterone, the embryo will remain female.
However, not much is known about how the influx and/or absence of certain chemicals in the womb consequently affects the gender identity that one associates with.
Rahman suggested that researchers should look into the crossover between physiological and psychological factors.
‘In some deeper sense, showing brain differences, or finding genetic differences, would not at all be surprising. The big question is how these biological influences shape the felt sense of gender identity,’ Rahman said.
‘How do prenatal sex hormones shape the developing brain circuitry which controls your sense of gender identity? Where is that network?’ he continued. ‘How does it work to make this happen and how does it map out over time, from early childhood to middle childhood through to adolescence and young adulthood? And how does that become different in some people to the sex they were assigned at birth?’
On the other hand, there is also the ‘nurture’ part. Past research have shown that social conditioning can affect gender identity.
For instance, an intersex person who receives ‘treatment’ early to become female tends to grow up feeling female, and vice versa.
A person’s sexual identity can also be viewed as the sum of four related aspects: 1. one’s biological sex; 2. one’s sexual orientation; 3. the gender one relates to; and 4. the gender that dominates one’s behavior.
‘There are going to be people on any part of any of those four different spectra,’ said Robin Lovell-Badge, the head of stem cell biology and developmental genetics at the Francis Crick Institute in London. ‘So it’s difficult to have terminology which is going to really fit with everyone.’
H/T: The Guardian