Prenatal Diagnosis of Ornithine Transcarbamylase Deficiency with Use of DNA Polymorphisms

ORNITHINE transcarbamylase is a hepatic urea-cycle enzyme that is required for the detoxification of ammonia and the biosynthesis of urea.1 Human ornithine transcarbamylase deficiency, an X-linked disorder,2 , 3 results in severe and often fatal neonatal ammonia intoxication in hemizygous affected males. The neurologic outcome in affected boys who survive the neonatal period is poor; they have a high incidence of mental retardation, cerebral palsy, and seizure disorders.4 Prenatal diagnosis of ornithine transcarbamylase deficiency has been difficult because the enzyme is not expressed in amniocytes and because no metabolic products of this disorder have been detected in amniotic fluid. Prenatal diagnosis by . . .