6-7-go-to-hell-or-go-to-heaven:
Idk, I don’t think sexual orientation is determined by any one thing. There might be a genetic basis, there might be a gestational hormonal basis, it could be wiring somewhere in the brain, maybe environmental factors play a part too. Could be all of the above and more.
The why/how isn’t something I care about in the slightest really, I just know it isn’t something that can be changed or influenced and that’s the only thing that matters.
Identical twins aren’t truly genetically identical though. They receive the same alleles from each parent but so many types of genetic recombination is happening during development in the womb that they end up differing from each other on a genetic level significantly.
Their fingerprints in the majority differ significantly from each other for example. Having almost identical fingerprints or even identical ones is a rarity in itself amongst identical twins for the former and improbable for the latter .
And that doesn’t even account for the environmental factors that can impact gene expression and can ultimately change a phenotype and all the phenotypical variation that stems from it. Epigenetics is a comparatively newborn field in genetics .
Calling them monozygotic twins is more accurate. They came from the same zygote but ultimately their development followed different paths. The determination of many human traits are highly complex and we are still identifying them. Studying Height alone on a genetic level , they have identified almost 10000 different DNA markers that can influence height development and there are propably even more genetic markers we haven’t determined yet.
There’s no “gay gene”. There are a multitude of genetic markers we have only started to identify. Human traits are rarely Straightforward determined by the expression of one gene.
I think sexuality is the most immutable of human traits. Funnily enough it seems to be the most resistant to environmental factors. Even the color of your eyes can change throughout your life time. Sexuality on a fundamental level doesn’t(if thousands years and still ongoing torture from all sides can’t “change” it i don’t know what could, like women can never change their sex to escape this hellhole of a world , Homosexual people can’t become Bisexual or Heterosexual either ). And the instances of “changed” or “fluid” sexuality are just Bisexuality. They are the only ones that can fluctuate between the sexes.
There are studies on monozygotic twins where there is an increased likelihood of them sharing the same Sexuality(be it hetero , Homosexual or Bisexual). Even amongst siblings from different zygotes when one is Homosexual/Bisexual there’s an increased likelihood of the other siblings to be Homosexual/Bisexual too. And regular siblings inherit different genetic material from the start. And in the womb during development they undergo as many changes that makes them even more genetically distinct prior to the subsequent mitosis of the zygote. It’s straightforward why they can have different sexualities.
