Biochemical studies in a patient with chromatin-negative klinefelter's syndrome

Abstract

The metabolism of [ 3H]dehydroepiandrosterone and [4- 14C]progesterone by homogenates of testicular tissue obtained from a patient with the features of chromatin-negative Klinefelter's syndrome has been studied in vitro. In these conversion studies, [ 3H] Δ 5-androsten-3 β,17 β-diol was the only metabolite detected in the incubates. When minced testicular tissue was incubated, a small amount of testosterone was produced in vitro, and no significant rise occurred in the presence of human chorionic gonadotrophin. By contrast, the patient's plasma testosterone level was below the normal male range, and showed a marked rise following administration of human chorionic gonadotrophin. These studies suggest a 3-β-hydroxysteroid dehydrogenaseisomerase deficiency in this disorder and demonstrate that the capacity of the testis to secrete testosterone in vitro is extremely small and unresponsive to human chorionic gonadotrophin.