Reproductive System IV (Disorders of Sex Development)

Question 1

What is the chromosomal, gonadal, and phenotypic sex of someone with Turner Syndrome?

Answer 1

Chromosomal: X0
Gonadal: Ovaries (no SRY)
Phenotypic:
- Internal: Mullerian duct (no testosterone/AMH)
- External: Feminized (no DHT)

Question 2

Extra details about Turner Syndrome:

Answer 2

Cause: abnormalities in mitosis and meiosis during oogenesis or spermatogenesis.

“Streak” ovaries: Small. Amenorrhea, infertility.
Short stature. Webbed neck. Abnormalities in vessels and valves. Horseshoe kidneys - connected.

Question 3

What is the chromosomal, gonadal, and phenotypic sex of someone with Klinefelter Syndrome?

Answer 3

Chromosomal: XXY
Gonadal: Testes (SRY present)
Phenotypic:
- Internal: Wolffian duct (testosterone and AMH)
- External: Masculinization (DHT)

Question 4

Extra details about Klinefelter Syndrome.

Answer 4

Cause: abnormalities in mitosis and meiosis.

Additional X chromosome result in narrower shoulders, wider hips, breast development, low testosterone, female-pattern pubic hair, poor beard growth.

Can intervene in-utero with growth hormone for more normal development.

Question 5

What is the chromosomal, gonadal, and phenotypic sex of someone with Androgen Insensitivity Syndrome?

Answer 5

Chromosomal: XY
Gonadal: Testes INSIDE of body (SRY Present)
Phenotypic:
- Internal: NO Wolffian or Mullerian duct (AMH binds, but not testosterone)
- External: Feminization (DHT can’t bind)

Question 6

Extra details about Androgen Insensitivity Syndrome:

Answer 6

Cause: mutation in androgen receptors. Cannot respond to testosterone.

Amenorrhea. Extremely smooth skin, no acne.
Likely not discovered till maturation. Testes removed surgery to prevent cancer. Hormone replacement therapy.

Question 7

What is the chromosomal, gonadal, and phenotypic sex of someone with Congenital Adrenal Hyperplasia (CAH)?

Answer 7

Chromosomal: XX
Gonadal: Ovaries (No SRY)
Phenotypic:
- Internal: Mullerian (no AMH) and Wolffian duct (sustained by testosterone)
- External: Feminization, partial masculinization (enlarged clitoris)

Question 8

Extra details about CAH:

Answer 8

Cause: excess testosterone production from adrenal gland (Zona reticularis).