First Trimester Diagnosis in a Twin Pregnancy in Which the Mother is a Proven Carrier of the X-Linked Disorder Menkes’ Syndrome

Abstract

Menkes’ syndrome is a genetically determined disturbance of copper metabolism, showing X-linked inheritance. Prenatal diagnosis has until quite recently been based on incorporation studies of labelled copper into cultured amniotic fluid cells (Horn 1981). The diagnosis of Menkes’ syndrome is now possible by direct copper analysis of trophoblastic tissue (Horn et al., this volume). The chorionic villi of an affected male fetus showed copper concentrations 40 times higher than those of normal controls (Horn et al., this volume). Because of random X chromosome inactivation in placental tissue of carriers, the trophoblastic tissue of female fetuses may however also show high copper levels (Damsgaard et al. 1983). In dizygotic twin pregnancies, it is therefore of importance to obtain pure samples from the fetuses in order to avoid the risk of a misdiagnosis. We report here on a successful first trimester diagnosis in a dizygotic twin pregnancy at risk for Menkes’ syndrome.