Sex is determined by chromosomes during fertilization. In the early stages of human development, a human embryo has the precursors of female (paramesonephric or Müllerian ducts) and male (mesonephric ducts or Wolffian) gonads. If a Y chromosome is lacking, or defective as seen in Swyer syndrome, the embryo will reabsorb the mesonephric ducts and proceed with paramesonephric ducts, which give rise to ovaries. The Y chromosome contains a sex-determining region called the SRY gene. Thus, the developmental plan of the embryo is altered only if this gene is present and functional. Mutations affecting the androgen receptor (AR) gene may cause either complete or partial androgen insensitivity syndrome. Androgens are a group of hormones which regulate the development and maintenance of male characteristics. Between 8 and 12 weeks, human male fetuses become externally distinct as androgens enlarge the phallus and produce a penis with a urethra and scrotum. Persistent Müllerian duct syndrome is a form of<unk> , developed through Müllerian-inhibiting factor defects. In such instances, duct derivatives are present in males, including the uterus, fallopian tubes, and upper vagina.
Pseudohermaphroditism
Microorchidism
Loxoscelism
Polyorchidism
Hypogonadotropic hypogonadism
Hypergonadotropic hypogonadism
Gonadal dysgenesis
Adiposogenital dystrophy