Clinical, endocrine, and molecular genetic findings in patients with 17beta-hydroxysteroid dehydrogenase deficiency.

Mutations in the 17beta-hydroxysteroid dehydrogenase (17beta-HSD) type 3 gene are associated with the clinical findings of 17beta-HSD deficiency. We investigated 5 patients of German descent with 46,XY karyotype and predominantly female phenotype. Androstenedione (A) and testosterone (T) levels in serum were determined before and after stimulation with human chorionic gonadotropin. DNA analysis of the whole coding region of the 17beta-HSD type 3 gene was performed by PCR, single-strand conformation analysis, and direct sequencing. In all patients we found highly variable A and T levels before and after stimulation. However, the A-to-T ratio was abnormal in all cases suggestive of 17beta-HSD deficiency. Molecular genetic analysis revealed mutations in all patients. We conclude that A and T levels may be highly variable in patients with 17beta-HSD deficiency. Molecular genetic analysis of the 17beta-HSD gene may support the diagnosis of this disorder.