Question

A 46-XX female fetus has a mutation that causes her to produce excess 5-alpha reductase. What would you expect to be different at birth and why?

b. How will this change at puberty and why?

Answer 1

Concept:- both estrogen and dihydrotestosterone have a common substrate called Testosterone which is formed from cholesterol.

Normally In females this testosterone is converted into estrogen by aromatse .

And in male it is converted into DHT by 5 alpha reductase.

A

Now as in the given case level of 5 aplha reductase is high so it will lead to conversion of testosterone to DHT in female feotus also.

This will lead to masculinisation of female foetus. With ambigous genitalia at birth.

As female reaches puberty she will develop male like ambigous genitalia.

Body and facial hair, male lattern pubic hair. Hirsutism , deep voice like male.

In short she will have ovary and uterus as intern organ , but her external organ will have a apperance of male character.