Does having an older brother make you gay?

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New research has suggested that having an older brother may make you more likely to be gay.

According to a study published in Canadian scientific journal PNAS, scientists have potentially identified a biological cause for being gay and apparently down to being a younger sibling.

Researchers from six different institutions across Canada and the United States worked together on the study.

According to the research: “Gay men have, on average, a greater number of older brothers than do heterosexual men, a well-known finding within sexual science.”

The researchers believe that the phenonemon is related to a protein related to the Y-chromosome, created when a male child grows in the womb.

Does having an older brother make you gay?
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According to the study, this protein then enters the bloodstream of the mother, which then causes her body to make antibodies in response.

These antibodies can then enter the body of any second sons during pregnancy, and may affect the way the sons experience attraction later in life.

Of course, it is important to note that not every person who can be pregnant is a woman, and not every person with a Y-chromosome is male.

The study claims that this affect is cumilative: the impact of the antibodies grows with each subsequent pregnancy, meaning that later sons are increasingly likely to be gay than their older siblings.

Does having an older brother make you gay?
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The exact reasons behind why some people are LGBT+ are not yet known, with many researchers believing that the causes are both biological and due to a person’s environment.

Researchers are hopeful that this study can help understand one of the many causes behind men being gay, though they stress that there needs to be further research.

This study follows earlier research publicised this week that claimed to find a genetic cause of being gay.

Scientists at Northshore University discovered that there are a number of genes that are far more common in gay men than their heterosexual counterparts.

Does having an older brother make you gay?
(Photo: RawPixel)

Addressing this new research, Professor Bailey of Northshore University said:”It is significant, and I believe science granting agencies should put a high priority into additional research to see if this is true.”

Earlier this year, Professor Jenny Graves wrote on PinkNews that “the claim that homosexual men share a ‘gay gene‘ created a furore in the 1990s.