Homosexuality is not predetermined by genes 

New work of scientists from the University of Queensland has
established that certain genetic patterns do exist in gays, but
they are not unique only for people with homosexual behavior.
In fact, heterosexual people with excessive sexual activity also
have similar genetic patterns. Nature writes about the findings
of the study.
(https://www.nature.com/articles/d41586-021-02312-0) 
To come to this conclusion, scientists analyzed the genomes 
of 477 thousand people who had at least one sexual experience
with a representative of the same gender, and then compared
the data with genomes of 358 thousand people with heterosexual
behavior. In addition, they modeled evolution over 60 generations
to trace characteristic patterns. It turned out that many of the
genetic variants associated with homosexual behavior would
disappear over time if they did not help people survive and
reproduce. Further observations showed that the discovered
genetic patterns provided an evolutionary advantage by increasing
the number of sexual partners in humans. Scientists have found
that people with homosexual behavior share common genetic
biomarkers with people with dissolute heterosexual behavior who
described themselves as "risky". The latter had more sexual
contacts with members of the opposite sex and more children.
From an evolutionary perspective, it becomes clear why the
persistence of these genetic patterns was maintained, the scientists
concluded. Earlier in another major study published in Science, 
https://science.sciencemag.org/content/365/6456/eaat7693, 
scientists also denied the existence of the "homosexual gene." 
They found no genetic pattern that could be used to identify a
person's sexual orientation.