Altered transcription profiles of key-enzymes of androgen biosynthesis in genital skin fibroblasts from patients with 46,XY disorders of sex development (DSD)

Normal synthesis and action of androgens is essential for normal male sex differentiation. 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) and 5 alpha-reductase isoenzymes play essential roles in normal androgen biosynthesis. We hypothesized that differences in expression of these enzymes in genital skin could contribute to the pathogenesis of 46, XY disorders of sex development (DSD). We investigated the mRNA transcription patterns of 17 beta-hydroxysteroid dehydrogenase-isoenzymes type 1, 2, 3, 4, 5, 7, and 10, 5 alpha-reductase type 1 and 2 and the androgen receptor in genital skin fibroblasts from foreskin and scrotal skin obtained from healthy males and patients with unclassified 46, XY DSD. mRNA expression was semi-quantified by real-time PCR. Although no systematic differences of gene expression of any enzyme between normal controls and hypospadias patients could be detected, we found in nearly half of all investigated patients' samples noticeable differences in the transcription profiles of 17 beta-hydroxysteroid dehydrogenase type 5. In scrotal skin samples of patients a significantly higher transcription of the androgen receptor was detected. A role for an altered expression pattern of different enzymes of steroidogenesis in the etiology of genital malformations in some patients may be postulated. Copyright (C) 2007 S. Karger AG, Basel.