Gay gene

An article in the Daily Mail suggests that there is no such thing as a single gay gene.

https://www.dailymail.co.uk/sciencetech/article-7407123/Scientists-homosexuality-caused-combination-environmental-genetic-factors.html

Preference for same-sex relationships is determined by both environmental and assorted genetic factors, a large-scale study has confirmed. This means that there is no such thing as a single 'gay gene' that determines your sexual preferences — just like many other human traits. 
Instead, thousands of genetic regions are involved, together accounting for between around 8–25 per cent of variation in sexual preferences between people.
Researchers confirmed this after studying genetic and survey data from over 470,000 volunteers taken from the UK Biobank and 23andMe.com.

Perhaps researchers should look at the Davies Hypothesis which suggest that attraction to the same sex is due to the character inherited by a child in the womb. This character need not be from the recent past but may come from many generations prior. The inherited character will also have inherited a character, perhaps from many generations before etc. At each emergence the final character will be moulded by nurturing ensuring the child is of the present time.
Whereas nature tries to match a character with the sex of the foetus, circumstances can lead to a female character with a male body and vice versa. This means that over time, everybody has some characteristic of the other sex to greater or lesser degree.
So what determines nature's predilection? I suggest it is to do with the lunar cycle at the point of conception. For more information and detail I refer readers to my book: Spiritual Man: An Introduction to Negative Dimensions.