What is the latest consensus on the causes of sexuality?

Question

In 2019, scientists concluded that there is no gay gene. Epigentic markers of homosexuality have been disproven. The Exotic becomes Erotic Theory is an ancient decrepit idea that holds no water. Yet, scientists think that it may have a genetic component. However, we simply cannot find it. I find this very odd and was wondering if there were any studies (as of December 2021) that could shed some light on why some people are gay, straight, bisexual etc.

https://www.pbs.org/newshour/amp/science/there-is-no-gay-gene-there-is-no-straight-gene-sexuality-is-just-complex-study-confirms

Rather than sexuality which definitely has a genetic basis - without which the species would die out, are you perhaps referring to sexual orientation? Could you point to the studies that you claim "disprove" a genetic or epigenetic connection to show us evidence of your prior researches as per our requirements laid-out in the [help]. Please also take our [tour]. — Jiminy Cricket., Dec 11 '21 at 19:10
Certainly. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0014821 — Aaron, Dec 11 '21 at 19:56
It was cited as such. I didn’t read the full article.
I think you are being a little draconian. This is my first time posting on stackexchange biology — Aaron, Dec 11 '21 at 20:16
For what it's worth, there is never such a thing as a "something gene", that's just not how it works. All humans have the same complement of genes and this is a classic misconception in media reports on genetic issues. Can you explain what it is you say that "scientists" concluded in 2019? Can you also explain how the paper you linked to is relevant? That seems to be a study on ageing, and specifically how epigenetic modifications change with age, so I don't see the connection to your question. — terdon, Dec 11 '21 at 20:39
As currently written your post suggests you lack the background to understand a real answer. Your source says "There is no gay gene" — what do you think you are supporting by adding that source? Science is a process not a body of "facts" — you will have a much better experience here if you do some additional reading and make sure you understand the basics of genetics (or if you do have that background, then make that clear by not using pseudoscientific terms like "gay gene"). In addition, you really must provide references for strong claims such as your second sentence. — tyersome, Dec 11 '21 at 22:53
there is no one gene controlling X, and X has no genetic basis are two very different things. height has no single gene but it certainly has a genetic component. there is also such a thing as triggered genetic elements, a male has all the genes to make a female and a male, but only one set of genes gets triggered. many genes are like this, everyone may well have the genes for every sexual orientation just as they have the genes for testes and ovaries. — John, Dec 12 '21 at 05:51

anongoodnurse · Answer 1 · 2021-12-11T22:19:03.730

You are correct. The Nature article to which you refer does contain the line, "There is no gay gene." But that can't be, and is not, the conclusion. In context:

The largest study to date on the genetic basis of sexuality has revealed five spots on the human genome that are linked to same-sex sexual behaviour — but none of the markers are reliable enough to predict someone’s sexuality. The findings, which are published on 29 August in Science and based on the genomes of nearly 500,000 people, shore up the results of earlier, smaller studies and confirm the suspicions of many scientists: while sexual preferences have a genetic component, no single gene has a large effect on sexual behaviours. “There is no ‘gay gene’,” says lead study author Andrea Ganna, a geneticist at the Broad Institute of MIT and Harvard in Cambridge, Massachusetts. Ganna and his colleagues also used the analysis to estimate that up to 25% of sexual behaviour can be explained by genetics, with the rest influenced by environmental and cultural factors — a figure similar to the findings of smaller studies. “This is a solid study,” says Melinda Mills, a sociologist at the University of Oxford, UK, who studies the genetic basis of reproductive behaviours. [Emphasis mine; punctuation changed for formatting reasons.]

In stating, "There is no gay gene", you commit the offense that many journalists do when quoting scientific study results: you cherry-picked the sensational sentence, which misrepresents the entire paper.

The second paper you use as a source simply summarizes the original paper, which states,

Same-sex sexual behavior is influenced by not one or a few genes but many. Overlap with genetic influences on other traits provides insights into the underlying biology of same-sex sexual behavior, and analysis of different aspects of sexual preference underscore its complexity and call into question the validity of bipolar continuum measures such as the Kinsey scale.

People cherry pick for several reasons, some innocent, some less so. In 1999, Gur et al published a study on white and gray matter distribution in men vs. women doing certain tasks, revealing a difference. The result: headlines shouting that men really were different than women, and that men had more of the matter associated with logical processing than women. This was a complete misrepresentation of the findings, ignoring that this only pertained to brain usage during certain tasks. Some people used this oversimplification to support their bias that men were smarter than women.

Interpreting scientific articles is sometimes very complicated. Any attempt to boil it down to one take away - other than "it's complicated" - is usually wrong.

I read most of the article. Yes it’s more complicated than just saying “there is no gay gene” but when you are done reading; to sum it up; yes, sexuality cannot be determined by one singular genetic component. — Aaron, Dec 11 '21 at 22:39
@Aaron Of course the important context is that very, very little can be determined by one singular genetic component, beyond the molecular level. The examples that can are quite unusual and highly notable; that's what the authors are expressing: they have not been able to identify one of those notable, unusual exceptions. — Bryan Krause, Dec 11 '21 at 23:55
@Aaron - It takes more than 100 genes to determine hair color. So, I would be correct in saying, "There is no single gene responsible for hair color." That is very different than saying/proclaiming, "There is no hair color gene!" — anongoodnurse, Dec 12 '21 at 00:28

score 2 · Accepted Answer · answered Dec 11 '21 at 22:37

On the epigenetics of sexual preference, please see the following:

Balthazart, J. (2020). Sexual partner preference in animals and humans. Neuroscience & Biobehavioral Reviews, 115, 34–47. https://doi.org/10.1016/j.neubiorev.2020.03.024
Balter, M. (2015). Homosexuality may be caused by chemical modifications to DNA. Science. https://doi.org/10.1126/science.aad4686
Wikimedia Foundation. (2021, November 2). Epigenetic theories of homosexuality. Wikipedia. Retrieved December 11, 2021, from https://en.wikipedia.org/wiki/Epigenetic_theories_of_homosexuality.

First article is great. Thank you very much! – Aaron Dec 12 '21 at 00:46 — Aaron, Dec 12 '21 at 00:46

What is the latest consensus on the causes of sexuality?

2 Answers2