Parents

HNRNPU-Related Neurodevelopmental Disorder (RNDD) is a rare neurodevelopmental disorder characterized by mild to severe developmental delay/intellectual disability, epilepsy and seizures, speech and motor skills delay, behavioral differences such as autism spectrum disorder, hypotonia (low muscle tone), and subtle but distinctive facial features. Other features observed in some HNRNPU-RNDD patients include brain imaging/MRI differences, congenital heart defects, and growth delay or short stature.

HNRNPU-RNDD is typically the result of de novo variant, meaning that it is absent from either parent.

It is estimated that HNRNPU-RNDD, or a de novo HNRNPU variant, occurs in about 1 in 55,000 individuals. Over 300 individuals have been published in the medical literature.