We may know why younger brothers are more likely to be gay | New Scientist

Contents:

• HAVG OLR BROTHERS INCREAS A MAN'S ODDS OF BEG GAY
• HAVG OLR BROTHERS CREAS MEN’S LIKELIHOOD OF BEG GAY
• MEN WH OLR BROTHERS ARE MORE LIKELY TO BE GAY, STUDY SUGGTS
• PEOPLE WH OLR BROTHERS MORE LIKELY TO BE GAY, ACRDG TO SCIENCE
• BORN THIS WAY: WHY HAVG AN OLR BROTHER MAK MEN MORE LIKELY TO BE GAY
• ARE YOUNGER BROTHERS MORE LIKELY TO BE GAY?
• STUDY SUGGTS MAL WH OLR BROTHER MORE LIKELY TO BE GAY
• WE MAY KNOW WHY YOUNGER BROTHERS ARE MORE LIKELY TO BE GAY
• MEN WH OLR BROTHERS MORE LIKELY TO BE GAY
• BLOGIL VERS NON-BLOGIL OLR BROTHERS, AND MALE GAY ORIENTATN

HAVG OLR BROTHERS INCREAS A MAN'S ODDS OF BEG GAY

The number of blogil olr brothers a boy's mother has rried--whether they live wh him the same hoehold or not--affects his chanc of beg gay.

In the new study, Bogaert pted prenatal agast postnatal by examg four sampl of homosexual and heterosexual men, for a total of 944 participants. First, wouldn't matter whether a gay man's olr brothers had been blogilly related or not, the social fluence would be there.

Send, his study showed that the amount of time reared wh olr brothers--eher related or not--did not predict a young boy's beg homosexual. And surprisgly, Bogaert disvered that even if a young man did not grow up the same hoe as his olr brothers, the fact that he had olr blogil brothers creased his odds of beg gay. Earlier studi have noticed that gay men often have olr brothers.

HAVG OLR BROTHERS CREAS MEN’S LIKELIHOOD OF BEG GAY

If you’re a guy wh an olr brother, there’s an creased chance you’re gay. The rearchers say that if their fdgs n be replited, we may know at least one of the blogil reasons some men are gay. A 2006 study showed that wh each brother, the chance that a man will be gay go up by about a third, but the rearchers didn’t terme why that was.

MEN WH OLR BROTHERS ARE MORE LIKELY TO BE GAY, STUDY SUGGTS

They found the hight ncentratn of antibodi to the prote women wh gay younger sons who had olr brothers, pared wh women who had no sons or who had given birth to only heterosexual boys. One found that a man’s chanc of beg gay creased even if he was raised apart om his olr brother. The rearch do not give a blogil explanatn for why some men may be bisexual or may not be attracted to anyone at all, nor n give a blogil explanatn for gay only children, gay olst sons or women who are attracted to women.

Bailey’s latt paper, published this month the journal Nature Rearch, looked at people’s genom and found several regns wh sgle-letter DNA chang that were more mon among gay men than straight men and may be relevant to the velopment of sexual orientatn. Men wh olr brothers are more likely to be gay, acrdg to a study published Wednday the journal Proceedgs of the Royal Society B.

PEOPLE WH OLR BROTHERS MORE LIKELY TO BE GAY, ACRDG TO SCIENCE

This new report builds upon prev rearch regardg male birth orr and homosexualy, though there is still no cisive ncln as to why there’s a lk between the cross-analyzg data om 10 scientific studi wh more than 5, 000 subjects, rearchers found that men wh olr brothers were 38 percent more likely to intify as gay.

”The study, which pared the probabily of the youngt brother a two-son fay beg gay as pared to the olst son, did not clu female subjects, as prev rearch has tablished that women do not fluence the sexual orientatn of their younger siblgs, acrdg to this study did not terme a ncrete reason for the rrelatn between a man havg an olr brother and intifyg as gay, Blanchard said that “pots toward the need for more rearch on the 'maternal immune hypothis'” — a theory Blanchard troduced 1996 that suggts that a mother is exposed to “male-specific substanc” durg pregnancy wh or the birth of a son. Acrdg to proponents of the theory, the mother’s immune rponse is changed durg the pregnancy of a boy, creasg the likelihood that a subsequent male child would be gay.

BORN THIS WAY: WHY HAVG AN OLR BROTHER MAK MEN MORE LIKELY TO BE GAY

Rearch nfirms 'aternal birth orr effect' for homosexualy — Men wh olr brothers are more likely to be gay.

Havg an olr brother uld be why you’re gay. A new study claims to have found pellg evince for the theory that people who have olr brothers are more likely to be gay, known as the “aternal birth orr effect”. A new study, published this week the Journal of Sex Rearch, found “clear evince of a aternal birth orr effect on homosexualy”.

Although the data did not rerd the sexual orientatn of dividuals, did show which people had entered to same-sex marriag and civil partnerships, which rearchers ed “as a proxy for homosexualy”. “It also discreds claims homosexualy n be ‘tght’ (such as through sexual diversy tn at schools) or ‘passed on’ (such as through same-sex upl adoptg children)… Like others before , we nsir this rearch sential.

ARE YOUNGER BROTHERS MORE LIKELY TO BE GAY?

It is important to note that the same-sex soc-sexual behavr observed the study is distct om homosexual behavr bee s motivatn and purpose are social, said Jean-Baptiste Le, who studi primate behavr at the Universy of Lethbridge Canada and was not volved the new rearch. To be classified as te homosexual behavr, the form, motivatn and functn would all have to be sexual nature, he said. In the first-ever laboratory study of mothers of gay men, the rearch was prompted by more than two s of statistil data examg the 'olr brother effect' which shows that blogil olr brothers—but not olr sisters—crease the odds of homosexualy later-born mal.

The study, "Male Homosexualy and Maternal Immune Rponsivy to the Y-Lked Prote NLGN4Y, " was published Monday, Dec. The current study adds to the growg scientific nsens that homosexualy is not a choice, but rather an nate predisposn.

STUDY SUGGTS MAL WH OLR BROTHER MORE LIKELY TO BE GAY

The team of psychologists and immunologists tted 16 women wh no sons, 72 mothers wh heterosexual sons, 31 mothers of gay sons wh no olr brothers, 23 mothers of gay sons wh olr brothers, and a ntrol group of 12 men.

The team found that mothers of gay sons, pecially those wh olr brothers, had signifintly higher antibody levels to both forms of NLGN4Y than did the ntrol sampl of women, cludg mothers of heterosexual sons. However, the psychologist utns that the effects are most and the likelihood of a male child beg born gay is still small—even if they have multiple male siblgs. Male homosexualy and maternal immune rponsivy to the Y-lked prote NLGN4Y, Proceedgs of the Natnal Amy of Scienc (2017).

Study nfirms lk between the number of olr brothers and creased odds of beg homosexual (2017, December 12).

WE MAY KNOW WHY YOUNGER BROTHERS ARE MORE LIKELY TO BE GAY

Scientists believe they may now know why gay men tend to have more olr brothers. Basilly, what Bogaert and his llaborators found is that havg olr brothers creas the chanc a man will be gay. In 2006, they published a study showg that each addnal brother creased the chanc a man would be gay by about 30 percent; Popular Science reported on those fdgs.

Turns out that of the more than 100 mothers volved Bogaert's latt study, those who have had more than one son have particularly high levels of the antibodi their blood—pecially if one of those sons is gay.

For example, some believe that firstborn men might be ls likely to e out as gay, even if they are. "Fdg a blogil basis for sexual orientatn is not an vatn for anyone to start suggtg that beg gay is a disease or is somehow "treatable, " Bogaert emphasized. "In fact, Bogaert said unrstandg that there is a blogil basis to homosexualy may be beneficial to the gay rights movement.

MEN WH OLR BROTHERS MORE LIKELY TO BE GAY

The bate about whether homosexual men are born or ma is hotly ntted. Purans still sist that homosexualy is a “liftyle choice” (and a wrong one at that).

Many gay men will tell you they have been sexually attracted to other men sce they first noticed the difference between the sex.

BLOGIL VERS NON-BLOGIL OLR BROTHERS, AND MALE GAY ORIENTATN

But the ia that sexual orientatn is fixed before birth has been strengthened wh the trigug fdg that the more male babi a woman has borne, the greater the likelihood that any subsequent sons will be homosexual.

Tw studi suggt that homosexualy isn’t all down to the ….