Science
Older Siblings and Sexual Orientation Study
A new study suggests that older siblings may influence sexual orientation through their mother's immune system. The research provides further insight into the complex factors behind sexual development.
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New Scientist
It has long been observed that men with older brothers are more likely to be gay, but an association has also been found with older sisters. This sheds further light on how a mother's immune system may be involved in shaping sexual orientation
2026-09-16 15:50 UTC