👤 Nurgün Kandemir

17-β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is an important enzyme involved in the final steps of androgen synthesis and is required for the development of normal male external genitalia. 46,XY individuals with deficiency of this enzyme present a wide clinical spectrum from a female appearance of the external genitalia through ambiguous genitalia to a predominantly male genitalia with micropenis or hypospadias. This paper reports a one-year-old 46,XY patient with 17β-HSD3 deficiency who presented with female external genitalia and bilaterally palpable gonads in the inguinal region. The low T/Δ4 ratio after human chorionic gonadotropin (hCG) stimulation suggested 17β-HSD3 deficiency. A homozygous mutation, c.761₇₆₂delAG, was determined at the intron 9/exon 10 splice site of the HSD17B3 gene. To the best of our knowledge, this mutation has not been reported thus far, but its localization and type would imply a complete disruption of the 17β-HSD3 which may explain the phenotype of our patient. Show less

17-beta-Hydroxysteroid dehydrogenase type 3 (17betaHSD-3) converts delta4 androstenedione (A) to testosterone (T) in the testes. This enzyme plays a key role in androgen synthesis and it is essential for normal fetal development of male genitalia. 17betaHSD-3 deficiency is a rare cause of 46,XY disorders of sexual development. Here, we report a 16-year-old 46,XY patient with 17betaHSD-3 deficiency raised as a female and significantly virilized in puberty. A homozygous 7 base pair deletion on exon 10 was determined in HSD17B3 gene (c.777-783del_GATAACC). Our patient had one of the very rare mutations, which was previously unencountered in Turkish patients with 17betaHSD type 3, and she is the second reported case with this deletion. Show less