HSD17B3 and hypogonadotropic hypogonadism: Regarding the group with a defined diagnosis, androgen receptor defects (n = 25), 5α-reductase type 2 deficiency (n = 20), and hypogonadotropic hypogonadism (n = 12), including six with associated hypopituitarism, were found with higher frequencies, followed by the group of defects in testosterone synthesis that included one patient with HSD3B2 deficiency, one with CYP17A1 deficiency, and two with HSD17B3 deficiency.