The most important concept we need to embrace going forward is very simple; innate does not equate with immutable.

Many things about sexuality, human and otherwise, are innate to the individual. A person doesn’t choose their orientation; it is an aspect of their sexuality that is beyond choice and beyond conditioning.  Most people think of this as being genetic, but that is a gross simplification and in my opinion erroneous.

There is a growing body of evidence that suggests that while orientation is innate it is not a genetic trait. Consider that the case of identical twins, with the exact same genome, it is not unheard of for orientation to differ. Most people think that there is the genetic, the genes passed down to your from your parents, and the learned, but biology is much more complex than that.

For an analogy think of genes as the hardware in your computer. The hardware set definite limits on what can be done, but you may not use all of the hardware in every manner possible. There is in biology an aspect known as epigenetics, meaning literally above the genes. Epigenetics is the systems and signals that turn on and turn off the genes of an organism; in the previous analogy it is the operating system to the hardware. It is by way of the epigenetic systems than an undifferentiated cell, contained the genetics instructions for all of the body’s tissues can become a heart cell and not something else.

A new model explains the differences in human sexuality by way of epigenetics. That when certain epigenetics pathways are activated or deactivated a person can end up with an orientation such as straight or gay. (Though of course any real observation of human sexuality yields the immediate evidence that the results are far from binary.) It is not that there is a ‘gay gene’, but rather in some people the pathways activating sexual arousal to members of their own gender are activated instead of being left dormant. This plays into nature’s inherent conservatism. It is easier to give men nipples and inactivate them, than create complex pathways of development losing the nipples when the female will require them.

So far people might be think that genetics or epigenetics, this is a difference only in terms and scientific precision without any real world consequence, but they are quite wrong to assume that.

Epigenetics is a mutable characteristic. It can be changed, altered, and is quite plastic. In mice model we have already manipulated epigenetic makers. Follow where this might lead.

If sexual traits such as orientation and identity are epigenetics and epigenetics are subject to artificial manipulation then is may be possible, and quite soon, to identify and manipulate sexual aspects.

It is fashionable, and not at all wrong, to consider the whole range of sexuality when world-building in your science-fiction universe, but given this possibility the whole range may not exist in the future. I feel that if soon gain the ability to alter the epigenetics markers for sexual orientation, provided these models are correct, then we cause generations in the near future to me startlingly homogenous in their sexuality. However if the ability to identify and manipulate is further off, say 60 years or more, then society’s current course will produce different outcomes; yielding a universe with diverse LGBTQ people. The current generation? I have no faith in us. I think even a lot of socially liberal parents would behind closed doors and in secret make sure that their children as saved the ‘trouble’ with being gay, wiping out the sexuality.

This doesn’t even touch on the issues of transgendered person and the possibility that the issue of strongly identify with a gender other than the one you were born into may be subject to epigenetic manipulation. Which is the better course, surgical alteration to transform into the self-perceived gender, or altering the epigenetic structures and with it self-perception?

I do not profess to be so wise as to have the answer, but these are questions that I think we will have to answer and soon.