Bisexual male twins

Duration: 10min 16sec Views: 1901 Submitted: 16.06.2020
Category: Babysitter
The relationship between biology and sexual orientation is a subject of research. While scientists do not know the exact cause of sexual orientation , they theorize that it is caused by a complex interplay of genetic , hormonal , and environmental influences. Biological theories for explaining the causes of sexual orientation are favored by scientists. The influence of hormones on the developing fetus has been the most influential causal hypothesis of the development of sexual orientation. The presence of the Y-chromosome in males prompts the development of testes, which release testosterone, the primary androgen receptor-activating hormone, to masculinize the fetus and fetal brain.

Why Do Some Identical Twins Have Different Sexual Orientations?

Why Do Some Identical Twins Have Different Sexual Orientations?

A growing amount of research suggests that sexual orientation has a genetic basis. In fact, scientists recently identified two specific genes that appear to differ between gay and straight men [1]. If sexual orientation is indeed genetically determined, it would be tempting to assume that identical twins would always have the same orientation, right? If they have the exact same genes and our genes control our sexuality, this would seem like a pretty logical conclusion. Identical twins sometimes have different orientations. For example, one may be straight while the other is gay. So why is that?

Biology and sexual orientation

A growing amount of research suggests that sexual orientation has a genetic basis. In fact, scientists recently identified two specific genes that appear to differ between gay and straight men [1]. If sexual orientation is indeed genetically determined, it would be tempting to assume that identical twins would always have the same orientation, right? If they have the exact same genes and our genes control our sexuality, this would seem like a pretty logical conclusion. Identical twins sometimes have different orientations.
Authors: Frederick L. Whitam, Ph. Twin pairs in which at least one twin is homosexual were solicited through announcements in the gay press and personal referrals from to the present. Thirty-eight pairs of monozygotic twins 34 male pairs and 4 female pairs were found to have a concordance rate of Twenty-three pairs of dizygotic twins were found to have a concordance rate of