Schaaf-Yang Syndrome: A Real Challenge for Prenatal Diagnosis

Abstract

Schaaf-Yang syndrome (SYS) is a rare neurodevelopmental disorder caused by pathogenic variants in the MAGEL2 gene. It is usually a postnatal diagnosis in infants with muscular hypotonia and feeding difficulties. There are no cases diagnosed antenatally. During pregnancy, the most common findings reported are polyhydramnios and decreased fetal movements, which are relatively common and unspecific.We present one case of fetal clubfoot and clinodactyly in a fetus postnatally diagnosed with SYS, as well as a brief review of the prenatal findings associated with this syndrome.

Keywords: fetal hypotonia; magel2 gene; neurocognitive disability; prader-willi syndrome; schaaf-yang syndrome.