Androgens and male physiology the syndrome of 5alpha-reductase-2 deficiency.
Level 5 - mechanism / opinion, no new human data
Narrative review summarizing clinical, biochemical, and genetic features of 5alpha-reductase-2 deficiency
PubMed 12573814 · doi:10.1016/s0303-7207(02)00368-4
What was done
This narrative review summarizes clinical, biochemical, and molecular genetic findings regarding 5alpha-reductase type 2 deficiency and the physiological roles of dihydrotestosterone (DHT) in male development.
What was found
The abstract provides no quantitative data or specific sample counts. It describes that affected 46,XY individuals have high-normal to elevated plasma testosterone, decreased DHT, and an elevated testosterone/DHT ratio. Phenotypically, patients present with ambiguous external genitalia at birth but normal internal Wolffian differentiation (presence of epididymides, vas deferens, and seminal vesicles). Pubertal virilization occurs frequently alongside gender role changes. In adulthood, individuals exhibit a rudimentary prostate, diminished or absent facial/body hair, an absence of balding, and normal spermatogenesis if the testes are descended.
Why it matters
The syndrome demonstrates the essential requirement of DHT conversion for male external genital and prostate development, distinguishing its actions from direct testosterone-mediated differentiation.
Limits
The abstract provides a descriptive overview without details on review methodology, systematic search criteria, or specific quantitative ranges for hormone levels.
Cited by
- context In adolescence, the 5-alpha reduction of testosterone to DHT is necessary for sexual differentiation and full adult male maturity.