Research results that the probability that a man with an older brother is gay is 38% higher
In recent years,
A method yielding comparable estimates of the fraternal birth order and female fecundity effects in male homosexuality | Proceedings of the Royal Society B: Biological Sciences
Men with older brothers are more likely to be gay, study suggests
Study suggests males with older brother more likely to be gay
The research team collected data on sexual orientation and presence of siblings for 5,390 men from survey data on 10 sexual orientation studies already published and analyzed using meta-analysis. Was. As a result of analysis, men with a brother had a 38% higher probability of being homosexual than men without a brother. This tendency is stronger as the number of older brothers is larger, and men with three older brothers are twice as likely to be homosexual as compared to men without older brothers. On the other hand, the probability of being gay was constant, no matter how many brothers we had.
On the other hand, according to Ray Blanchard, the lead author of the study, `` previous research has shown that the existence of the sister does not affect the sexual tendency of the sister and brother. '' , Did not analyze the sexual orientation of 'Women with older sisters.' According to analysis, mothers who gave birth to gay boys more than once tended to be more prolific.
Based on the above results, the research team called '
'The hypothesis that boy-specific proteins form an immune response that affects the next boy's sexual orientation seems reasonable, but needs further study,' Blanchard commented.
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