Medically speaking, we don’t know the cause or causes of transgenderism. Researchers are looking into several areas of the causes. They are genetics, the brain, childhood sexual abuse by a same sex abuser and hormonal treatments. Let’s briefly look at each one of these.
Some people think that transgenderism is an inherited trait that people are born with. They claim its similar to eye color or skin color. They can no more not be transgender than a black person cannot be born black. But medical science hasn’t proved this. There is no transgendered gene just as there is no homosexual gene.
Current research indicates that while genetic variation may be a contributing factor, it is not caused by genetics1. A contributing factor is NOT a causative factor. For example, a contributing factor to alcoholism may be genetic but no one would say that genetics causes alcoholism2. And one can become free from alcoholism.
Human behavior, especially something like transgenderism, is NOT genetically hardwired into us. Transgendered people are NOT born this way. Quite often, this is a temptation that the person didn’t ask for or choose. Even though people may be tempted by transgenderism, they are still morally responsible for how they react to the temptation.
No amount of surgery, hormone injections or anything else will change someone’s DNA from a man’s to a woman’s (or vice versa). As you know, for humans, sex is determined by the presence of a Y chromosome — humans with an X and a Y chromosome are male and those with two X chromosomes are female. No current (or probably future) technology can replace a chromosome in all of our trillions of cells3.
1…Laura Erickson-Schroth, “Update on the Biology of Transgender Identity”, Journal of Gay and Lesbian Mental Health 17 (2013):154
2…Harish R. Krishnam, “The Epigenetic Landscape of Alcoholism”, International Review of Neurobiology 115 (2014):154
3…https://genetics.thetech.org/ask/ask35 (from Stanford University)