If you're a dude, that is.
It’s a strange question to ask and kind of seems to be bordering on ignorance. However, there is some science behind the idea.
The sexual orientation, desires, and urges of humans are quite a mysterious subject matter and no matter how much science tries to explain it, there always seems to be something that proves a promising theory wrong.
And it seems like researchers are wasting their time with the "older brother is gay" theory.
As of late, researchers have been stuck on an idea called the Fraternal Birth Order Effect. This theory suggests that men who have an older brother are more likely to be gay. In fact, the research suggests that with each older brother, the chances go up.
This theory only recognizes the brothers being biological and states that it doesn’t matter whether or not the siblings live together or apart. When it comes to the ladies, the theory holds no weight either.
“Assuming that a man without any older brothers has a 2 percent chance of being homosexual, a man with one older brother has a 2.6 percent chance; with two, three, and four older brothers, the chances are 3.5 percent, 4.6 percent, and 6.0 percent, respectively," Bailey says.
The article by Bailey’s team goes even further to explain the science behind their thought as they sum up another article by sex researcher Ray Blanchard.
“Male fetuses carry male-specific proteins on their Y chromosome, called H-Y antigens... these antigens promote the development of heterosexual orientation in males,” Blanchard says.
These antigens are not naturally in the female body, so a mother who is pregnant with a boy will experience them, “triggering the production of maternal antibodies.” These antibodies, in turn, “bind to the H-Y antigens and prevent them from functioning, which, in turn, impedes sexual differentiation of brain centers mediating male sexual orientation.”
If the mother continues to have male pregnancies, the antigens in her system will increase, raising the likelihood that the next child will be gay.
While there is some valid science behind this theory, nothing has actually been proven and the fact that this doesn’t work the same in females raises some questions.
Plus, there are plenty of gay guys out there who don’t have any older brothers at all. So, who really knows.