Anti-mullerian hormone receptor type 2 Anti-mullerian hormone receptor type 2 Anti-Mullerian hormone receptor type 2 is a protein that in humans is encoded by the AMHR2 gene. This gene encodes the receptor for the anti-Mullerian hormone (AMH) which, in addition to testosterone, results in male sex differentiation. AMH and testosterone are produced in the testes by different cells and have different effects. Testosterone promotes the development of male genitalia while the binding of AMH to the encoded receptor prevents the development of the mullerian ducts into uterus and Fallopian tubes. Mutations in this gene are associated with persistent Mullerian duct syndrome type II. Alternatively spliced
Fraternal birth order and male sexual orientation studies have demonstrated that the fraternal birth order effect does not operate through social or postnatal (e.g., learning or rearing or environmental) mechanisms; rather it is biological in nature and operates prenatally. It is also known that the fraternal birth order effect on male sexual orientation is unaffected by family dynamics, living with older brothers or learning. Fraternal birth order and male sexual orientation A correlation between fraternal birth order and male sexual orientation has been suggested by research. Ray Blanchard identified the association and referred to it as the fraternal birth order effect. In several studies, the observation is