Is there actually something wrong with homosexuality?

How does homosexuality come about?

There is still no final explanation. It looks like homosexuality is innate in a certain way, but it is not inherited directly. What one can say in any case: It arises neither through socialization, nor through upbringing, nor through “seduction”. The idea that you become a lesbian because you see lesbian couples or gay because people talk about gays in class is scientifically completely unfounded.

There is no such thing as a "gay gene"

Homosexuality, it looks like, is biological. But that doesn't mean that there is such a thing as “gay genes”. In fact, researchers have been looking for genes like this for years - but they haven't found anything. If you think about it, it seems logical, because gays and lesbians can have biological children, but this happens much less often than the proportion of homosexuals in the population. That is 5 to 7 percent. Most homosexuals have heterosexual parents.

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At the moment, many researchers are looking for the trigger elsewhere: not directly in the parents' genes, but in pregnancy. That is, under certain circumstances certain genetic switches are turned on or off. Homosexuality would therefore not be genetic, but epigenetic conditionally. In simple terms, epigenetics investigates how genes are activated or deactivated.

There are several guesses here as to how to imagine this. One goes like this: Years ago it was noticed that gay men more often than the average have at least one older brother - even if this brother grew up somewhere else.

Immune Response During Pregnancy

At the end of 2017, researchers found a possible explanation for this on the basis of blood tests in the mothers: Male embryos trigger a certain immune reaction in the mother. As a result of this pregnancy, the maternal body produces antibodies. During a second pregnancy, these antibodies act on the younger brother, more precisely: on the switches in his brain that later determine sexual orientation.

However, it is clear that this mechanism cannot explain homosexuality on its own. After all, not every gay person has an older brother. So there must be other causes as well.

Epigenetic explanations

There is another - also epigenetic - explanation. It is based on the knowledge that epigenetic information - i.e. the states of activity of genes - can also be inherited under certain circumstances. If the sexual preference for women or men is a trait that is epigenetically determined, it is conceivable that it is also inherited.

So there could be a mechanism that ensures that in certain cases a father passes his sexual preference for women on to his daughter-to-be so that she becomes lesbian, and that, conversely, gay men have inherited the sexual preference for men from their mother.

Theory from several building blocks of knowledge

The scientists who came up with this theory put together several building blocks of knowledge. This means that what we call “gender” is made up of several components. There are those in physical sexual characteristics, there is social gender - which is also expressed in behavior - and there are sexual preference. The "standard case" is: In a male body there lives a male spirit with a sexual desire for women. But sometimes there is a different combination. That is why there are, for example, transsexuals who have the feeling that they are living in the wrong body. Homosexuals, on the other hand, have sexual preferences that differ from those of their heterosexual peers.

  1. This is the first building block of this theory: Gender identity is made up of several components. A sexual preference for women is usually inherited along with the “male” Y chromosome - but apparently not always. And vice versa, either.
  2. The second building block for the theory concerns the way in which the sex develops in an embryo. It's not like nature just looks to see if he has a Y chromosome and the entire masculinity results from it. But that In the case of men, the Y chromosome only sets the course. Then the hormones come into play, for example testosterone. This already happens in the womb. The gender-specific genes do not build the male or female body together, but rather they set certain switches in the body so that Under the influence of hormones, some develop embryos into males, others into female babies.
  3. This brings us to the third building block of the theory, the switches mentioned. It is a matter of Switches that decide whether certain genes are active or inactive. And thus also about which characteristics an embryo develops under the influence of the corresponding hormones. Normally these switch states are not inherited, but in some cases they are.

The course is set during pregnancy

This is where the aforementioned theory of the origin of homosexuality comes in. She says: Homosexuality arises when a heterosexual father passes on to his daughter exactly the switch state that creates a sexual preference for women in the brain of the embryo. Then the daughter develops into a lesbian. Conversely, in rare cases a mother can convey her sexual preference for men to her son - so that this son becomes gay.

So there are currently several explanations that - albeit in different ways - assume that the course will be set during pregnancy.

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