TL;DR People are who they are - sexuality is not a choice. They are just born that way, people are born gay.

As Lady Gaga once sang, 'you were born that way'. Sexuality is not a choice, we do not at a certain age just choose who we are attracted to. It is just what makes us as a person, it something that we are born with.

Sexuality is a complex subject of study. Study of genetics has confirmed that there is no 'gay gene', but equally there is no 'straight gene'. However, science does not need to be involved to explain the obvious, people of the LGBTQ+ community are who they are. Andrea Ganna, lead author and European molecular Biology Laboratory group leader stated that same-sex behaviour is just a 'natural part of our diversity as a species.' 'Natural' highlighting how being gay is not a choice.

Being gay or lesbian is simply a natural part of life. There is no conclusive evidence to prove if nature or nurture effects someone's sexuality.

As human beings, it should be accepted that there will be differences and variations within our species. Sexuality plays a part in this. People being gay or lesbian has always existed within society (even if laws prohibited the acts). This clearly shows that sexuality is not a choice but something that people are born being. Why would someone have chosen to be gay if they knew the law would severely punish them for it?

People of the LGBTQ+ community should be celebrated and accepted within society. They are born that way. It has never been a choice, and therefore procedures such as gay conversion should be banned and condemned.

tl;dr: There is no conclusive evidence as to what makes a person gay even by the APA, therefore it is likely a mix of both societal influence and nature.

The question of what makes someone gay remains largely unanswered.

The Royal College of Psychiatrists argue sexual orientation is determined by biological and post-natal environmental factors. While the American Psychological Association is in agreement that nature and nurture play complex roles.

With two of the world's greatest psychological institutions without a conclusive answer, it is impossible to be certain whether people's environment or biological nature is what makes them homosexual.

Some doctors (e.g. Dr J. Nicolosi) have argued for environmental factors determining why people are gay, arguing people without a strong mother figure in their life develop fantasies over males instead. The 'born gay' or 'gay gene' theory lacks credibility and evidence, this is not to say being gay is a choice, however it is highly likely that societal influences have a great role to play too.

TL;DR - People are born gay. Gay individuals can grow up in completely heterosexual environments. Therefore I find it hard to understand how society can have an involvement in someone's sexuality. Additionally, as Gay people are persecuted, I do not know anyone who would choose that persecution if it was a choice.

I completely believe people are born gay. I won't rehash the science or research studies as other people have done such a wonderful job, I just have a few comments.

Firstly, as a gay individual no-one else in my family or friendship circle when I was younger were LGBTQ+. Therefore, having spent much time in my youth thinking about it, I don't understand how it could have been learned or how it could be societal as all I knew through people close to me and the media was heterosexual relationships.

Additionally, in certain countries people are persecuted, tortured, stoned, killed, imprisoned, raped, forcibly impregnated etc. due to their sexuality. So I can't understand how they can't be born gay. I don't understand why they would be gay due to society and this idea of nurture over nature, as everything in their society persecutes gay individuals in the most horrific and torturous ways, so what would teach them in that society to be gay?

Additionally, in terms of some who have said it is a choice, whilst I love being gay, when growing up it would have been so much easier if I wasn't and would still be easier now. So in these countries why would people choose to put their lives and families lives in danger and make that choice? I don't know anyone who would choose that life if they had the choice.

TL;DR Sexuality is simply too complicated to reduce to biology or likewise the environment, for this reason it is important to consider the interaction of both together.

In some studies, in particular twin studies, it has been observed that sexual preference has a genetic component. For instance, a 1993 study in the [Journal of Science] (https://science.sciencemag.org/content/261/5119/321.abstract) showed that families with two homosexual brothers presented with the same genetic markers of the X chromosome, these findings thus prompted the discussion over the possibility of a ‘gay gene’, much like discussions surrounding both the ‘Warrior gene’ or ‘Alcoholism gene’. However, genes alone cannot be said to control behaviour, their regulation of amino acids and protein formation can influence the existence of certain traits but this is not to say they have complete control over them.

It is therefore necessary to consider the effects of the environment on the same behaviours and traits. Culture plays a large part in the acceptance of drinking alcohol and homosexuality for example, and this means some people are more, or less, likely to behave in a certain way. Environment, like genes, is seen to affect romantic relationships and throughout time, marriage has been greatly influenced by cultural beliefs and importantly, culture has been known to influence perspectives on homosexuality. In the West, society has progressed to widely accept homosexuality, but in other parts of the world, it is less tolerated and the death penalty is still in place in many countries, such as [Brunei, Saudi Arabia, Somalia and United Arab Emirates] (https://en.wikipedia.org/wiki/LGBT_rights_by_country_or_territory). The cultural beliefs surrounding someone as they grow up is likely to affect engagement in homosexuality and thus shows the importance of the environment in affecting behaviour.

The Prenatal Hormone Theory (PHT) of sexual orientation says same-gender sexual orientation stems from the underexposure of male fetuses or overexposure of female fetuses to androgens that are responsible for sexual differentiation.

This extraordinary paper shows AI can recognise sexual orientation from neutral photographs of faces with 91% accuracy for men and 83% accuracy for women. Our sexuality is encoded even in our outward physiognomy.

In fact, we are gaining a certain understanding of particular factors involved.

For instance, the first children are more often to be male or homosexual female. The more children the mother has, the less likely they are to be male, and if they are male, they are more likely to be homosexual the more males the mother has had.

This is because the female body doesn't recognize Y-chromosome traits and treats it as an invader. While an immune response is suppressed by other hormonal factors, it isn't entirely eliminated, and still gets better at attacking or modifying certain traits. One of which is sexual orientation.

So the more boys she has, the better her body gets at attacking or changing straight-male characteristics, so the less likely she is to have boys, and the more likely they are to be gay.

We gotta be careful here with the wording of the question. Homosexuality is not a choice, but that's not the question.

I really doubt that there is a literal "gay gene" so to speak.

I think sexual orientation is something you develop over time, not something you immediately are. A baby isn't immediately born and likes boys from the get go. A human being needs to live for a bit before they know what they really are. Some people do start of thinking they are a sexual orientation and later they prove they are that orientation but someone who is expected to like girls at a young age may eventually like the same sex due to behavioural development from exposure to their environment.

There may well be a genetic/hard-wired element to being gay but to say people are born that way is a step too far. Many things influence gayness, such as abandonment or abuse from Fathers for men or the same from partners for women.
Another factor to consider is that our attraction is very much culturally based. For instance marrying one's first cousin in Pakistan is pretty normal. The thought of it turns my western stomach and would for nearly every person in my culture but clearly it doesn't for them. The thought of marrying a man also fills be with the same disgust, but not for many people.
Likewise in some cultures tiny feet or huge lips are considered beautiful and attractive. These things show that attraction is always culturally conditioned and so I see no reason to believe that being homosexual does not also have an environmental factor to it.