Gonadal dysgenesis If a single or combination of these genes are mutated or deleted, downstream signalling is disrupted, leading to malformation of male external genitalia. SRY acts on gene SOX9 which drives Sertoli cell formation and testis differentiation. An absence in SRY causes SOX9 to not be expressed at the appropriate time or concentration, leading to a deficiency in testosterone and Anti-Müllerian hormone production. Inadequate levels of testosterone and Anti-Müllerian hormone disrupts the development of Wolffian ducts and internal genitalia that are key to male reproductive tract development. The lack of the male associated steroid hormones drives Müllerian duct development and perusal
Transgender hormone therapy (male-to-female) Transgender hormone therapy (male-to-female) Transgender hormone therapy of the male-to-female (MTF) type, also known as feminizing hormone therapy, is hormone therapy and sex reassignment therapy to change the secondary sexual characteristics of transgender people from masculine (or androgynous) to feminine. It is one of two types of transgender hormone therapy (the other being female-to-male) and is predominantly used to treat transgender women and other transfeminine individuals. Some intersex people also take this form of therapy, according to their personal needs and preferences. The purpose of the therapy is to cause the development of the secondary sex characteristics of the desired