Three gene finding studies showed that gay brothers share genetic markers on the X chromosome; the most recent study also found shared markers on chromosome 8. In many species, a prominent feature of sexual differentiation is the presence of a sexually dimorphic nucleus SDN in the preoptic hypothalamus, which is larger in males than in females. If this suggestion were correct same-sex orientations would decrease and disappear with time. This will make a gender-conforming child feel different from opposite-gender children, while gender-nonconforming children will feel different from children of their own gender. Some studies have enlisted participants who openly identify themselves as gay, who may not be typical of the entire homosexual population. The moral acceptability of homosexuality has often hinged on the idea that same-sex desires are innate and immutable and therefore not a choice.
Is There a 'Gay Gene'?
This can shed light on a possible genetic cause. By Kevin Mitchell - February 19, Female relatives of the homosexual men tended to have more offspring than those of the heterosexual men. Then Australia and the U. These studies differed significantly in how they assessed sexual orientation, however, which may be reflected in their results. The neuron count also found a male-female difference in INAH3, but found no trend related to sexual orientation. Those previous studies looked only at the genes located on the X chromosome.
Largest study of gay brothers homes in on 'gay genes' | New Scientist
About Us Care2 Team Blog. Current Opinion in Neurobiology. Leave a reply Cancel Reply You must be logged in to post a comment. It also raises privacy concerns that medical records could reveal sexuality.
Scientists find DNA differences between gay men and their straight twin brothers
Description: Slate logo Sign In Sign Up. In this context, it has been demonstrated that the female relatives of homosexual men have more children on average than women who do not have homosexual relatives. A child's temperament predisposes the child to prefer certain activities over others. I know someone who got on very well with their father, but couldn't stand their mother, but this person's sister was the complete opposite - the same went for the parents.