News > Research confirms same-sex attraction has a biological basis and your siblings matter
Research confirms same-sex attraction has a biological basis and your siblings matter
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The Indian Express | 11/02/2022 04:00 PM | Click to read full article
New research shows having a greater number of older brothers increases the probability of a person entering a same-sex union at some point in their lives.
The “fraternal birth order effect” is one of the most well-documented patterns supporting a biological origin of human sexual orientation. This longstanding hypothesis proposes men’s propensity for homosexuality increases with the number of older biological brothers they have.