Is homosexuality genetic?

[Eddie Dane]

I'm watching a mini series called the Manns, about the writer Thomas Mann.
(The series is great, I highly recommend it).

Mann had four children, two of them were gay.
He himself seems to have been bi-sexual or gay.

This made me think that there might be a inheritable component to sexual preference.

The funny thing, if this is true, is that the repression of gay people has led to many of them pretending to be straight, procreating, and thus leading to more gay people.

 

[Ian Osborne]

While it's far from impossible for a gay person to live as a heterosexual and have children, for obvious reasons, their rate of reproduction will obviously be lower than that of the general population. Surely this means the 'gay gene' would eventually die out?

 

[The_Fire]

First of all: Does it really matter?
Second: Take a look at BBC' episode on John Barrowman in the series "The Making of me". There are some interesting stuff about this (allthough I'm not sure about the measuring of fingers thing ).

There's speculation about wether or not having older siblings plays in (as a sort of natures way of making sure the older siblings have the upper hand), the chemical composition of the stuff you swim around in before you are born, genes, just about a little bit of everything.

And it's also determined that John Barrowmans brain is more like a womans than a mans in its reaction .That one had me chuckling quite a bit.

 

[The Don]

While it's far from impossible for a gay person to live as a heterosexual and have children, for obvious reasons, their rate of reproduction will obviously be lower than that of the general population. Surely this means the 'gay gene' would eventually die out?

All of the following presumes that there is a genetic element to sexual preference. The anecdote of Thomas Mann is just that, an anecdote, and unless there is a large body of evidence it's accidental or deliberate cherry-picking.

Haemophilia offers a significant disadvantage in terms of surviving to breed and yet it persists. If there is a genetic element to homosexuality, there's no reason to assume that it resides in a single gene or is attributable to a single parent.

 

[Eddie Dane]

First of all: Does it really matter?

No.

It just occurred to me watching the series.

In fact, I'd rather hope they didn't identify a specific gene or something.
People might try to engineer it out and future generations might have less Thomas Mann's or decent showtunes, for that matter.

 

[Ian Osborne]

All of the following presumes that there is a genetic element to sexual preference. The anecdote of Thomas Mann is just that, an anecdote, and unless there is a large body of evidence it's accidental or deliberate cherry-picking.

Absolutely.

Haemophilia offers a significant disadvantage in terms of surviving to breed and yet it persists. If there is a genetic element to homosexuality, there's no reason to assume that it resides in a single gene or is attributable to a single parent.

Yes, you're right - homosexuality could be genetic without relying on a 'gay gene'. Indeed, for reasons outlined in my previous post, it would probably have to.

 

[Darat]

...snip...

Yes, you're right - homosexuality could be genetic without relying on a 'gay gene'. Indeed, for reasons outlined in my previous post, it would probably have to.

You have to also take into account the society a person lives in is part of their environment. If the environment doesn't allow an expression of a certain behaviour that could prevent the "homosexual" genetic component from being winnowed.

Wasn't there some musings that homosexuality in aunts and uncles could help ensure that their genes are passed on via their nephew and nieces? Which would mean it was advantageous to those genes that contributed to such behaviour so the "homosexual gene" may not have only be conserved but actually selected for.

Interesting point if the above is true then now that there are not the environmental pressures in many societies and the advantage of having homosexual uncle and aunts has been nullified when it comes to reproduction you would expect the "homosexual gene" to start to die out...

 

[Cainkane1]

I'm watching a mini series called the Manns, about the writer Thomas Mann.
(The series is great, I highly recommend it).

Mann had four children, two of them were gay.
He himself seems to have been bi-sexual or gay.

This made me think that there might be a inheritable component to sexual preference.

The funny thing, if this is true, is that the repression of gay people has led to many of them pretending to be straight, procreating, and thus leading to more gay people.

Its only partly genetic. Scientists studying homosexuality say that a womans immune system may attack the male fetus and and damage some of the male hormone. This usually happens when the woman has had other male children.

http://youtu.be/yVliyerlQHE This video explains the latest theories.

Female homosexuality may be caused by an excess of male hormone in the womans womb and lesbians are usually the first oldest children in the family.

 

[SpecificImpulse]

Based on the limited data I've seen I would suspect it is epigenetic in nature. But that's just a guess.

 

[casebro]

If it was a simple, single gene thing, the gays would be trumpeting it form the mountain tops. The don't want it to be a 'choice' or their own 'fault'.

Epigenetics means genes that are usually un-expressed but are expressed in reaction to the environment. So probably not that.

The conditions in the mother's womb sound like a good theory. This is the first I've heard of lesbians being more often first-borns. So how soon before a amniocentesis test?

Hey, isn't baldness linked to excess of one type of testosterone? Any link between bald women and sexual preference of their children? ;^)

Or, with the commoness of birth control medications being estrogens, and polluting the water supplies, are more homosexuals being born today than previously?

 

[the PC apeman]

If it was a simple, single gene thing, the gays would be trumpeting it form the mountain tops. The don't want it to be a 'choice' or their own 'fault'.

This is not really a question of 'want'. We don't experience homosexuality as 'choice' or 'fault' any more than you (presumably) experience heterosexuality as 'choice' or 'fault'.

 

[The Fallen Serpent]

There is also the twin test. I forget the exact number but in studies twins share homosexuality something like 8 out of 10 times in comparison to left handedness which is shared in twins 7 out of 10 times. There are issues with the test, such as selection bias but it is considered a rough estimate of predicting likely genetic factors in shared twin traits.

Also keep in mind that a non-advantageous trait can still continuously crop up if it is a common mutation. For instance, which I know the evidence suggests mutiple factors genetic epigenetic and so on but I'm simplifying here, if a single gene controlled sexual orientation it would seem likely heterosexuality would be heavily selected for. However, if it was a rather small variable for such a gene to mutate into other forms of sexuality despite selective sexual pressure against such a changes these changes would continously reappear in progeny.

As stated by others there appears to be multiple contributing factors. Homosexuality also appears to have certain advantages to families and species even if it appears counter productive to continuing a direct paternal/maternal line with a superficial glance. This has been demonstrated in other similar social animals.

Is homosexuality genetic? From what I understand the evidence suggests it is at least partially. However from what I understood the evidence suggests the genetic potential for the full range of human sexuality appears fairly evenly across human bloodlines, that a homosexual has no more chance of having homosexual children than a heterosexual.

 

[Lamuella]

While it's far from impossible for a gay person to live as a heterosexual and have children, for obvious reasons, their rate of reproduction will obviously be lower than that of the general population. Surely this means the 'gay gene' would eventually die out?

not everything that causes individuals to not breed means that their genes will not be represented in subsequent generations. In any hive community, there are asexual hive members, and yet the hive persists because of kin selection. Without saying the two are directly comparable, I could imagine a circumstance where a non-breeding member of a community could allow it to survive better by giving them another pair of hands to work without giving them progeny to feed.

 

[Antiquehunter]

My understanding of the science to this point is that there may be a combination of factors - genetic & environmental. In addition to the studies already mentioned, I believe there were also some interesting results revealed in the birth order of kids, as well as other gay siblings in the family tree. (An uncanny number of gay men seem to also have a gay uncle, if I recall correctly.)

The comment that 'the gays want' this to be a genetic issue is ludicrous. Frankly, the last thing I would want is to be labelled some sort of genetic throwback, merely over the mundane issue of whom I prefer to share my bed.

 

[rjh01]

While it's far from impossible for a gay person to live as a heterosexual and have children, for obvious reasons, their rate of reproduction will obviously be lower than that of the general population. Surely this means the 'gay gene' would eventually die out?

Actually no. If under certain conditions it could be an advantage to have part of the 'gay gene' then you could have more children. For example a gay person could have raise the children of their brothers and sisters. Or it may protect the person from something.

 

[Complexity]

If it was a simple, single gene thing, the gays would be trumpeting it form the mountain tops. The don't want it to be a 'choice' or their own 'fault'.

Nonsense, and quite condescending.

I'm gay and want nothing but the truth.

I don't remember making a choice to be gay.

Since there is nothing wrong with being gay, there is no 'fault'.

Any other pearls of wisdom, while you're at it?

 

[Zeuzzz]

No, genetics is homosexual.

 

[Complexity]

No, genetics is homosexual.

Oddly enough, this is the most intelligible thing you've posted.

 

[Dessi]

If it was a simple, single gene thing, the gays would be trumpeting it form the mountain tops. The don't want it to be a 'choice' or their own 'fault'.

[off-topic]

Its kind of unfortunately that even people in the LGBT community validate that line of thought by arguing whether its a choice.

Anti-gay people have a created an entirely fabricated case that being gay is a choice, they then imply that a person can choose to be straight -- but why should they? Being gay is not immoral, there's no good reason why a person should choose to be straight, even if they could.

[/off-topic]

As for whether homosexuality is genetic, its interesting from a strictly scientific point of view.

I imagine there's probably a constellation of genes or characteristics that correlate with same-gender attraction, kind of the same way two parents with brown eyes can have children with green eyes and blue eyes.

 

[Paulhoff]

Yes it is genetic, not one tree is gay.

Paul