Zebra of the Week: Schaaf-Yang syndrome

Schaaf-Yang syndrome (SYS), also known as MAGEL2-related Prader-Willi-like syndrome, is a rare neurodevelopmental disorder caused by a change in the MAGEL2 gene. It's similar to the genetically related Prader-Willi syndrome and can also lead to its development. Infants with this syndrome can have hypotonia, feeding difficulties, developmental delay, intellectual disability, and autism spectrum disorder. They also typically have joint contractures, affecting the finger joints, knees, or elbows. However, SYS doesn't usually cause the high appetite seen in people with Prader-Willi syndrome.