Further evidence for de novo variants in SYNCRIP as the cause of a neurodevelopmental disorder.

1. September 2021

Semino F1,2, Schröter J1, Willemsen MH3, Bast T4,5, Biskup S6,7, Beck-Woedl S8, Brennenstuhl H9, Schaaf CP10, Kölker S9, Hoffmann GF9, Haack TB8,11, Syrbe S1


SYNCRIP encodes for the Synaptotagmin-binding cytoplasmic RNA-interacting protein, involved in RNA-binding and regulation of multiple cellular pathways. It has been proposed as a candidate gene for neurodevelopmental disorders (NDDs) with autism spectrum disorder (ASD), intellectual disability (ID), and epilepsy. We ascertained genetic, clinical, and neuroradiological data of three additional individuals with novel de novo SYNCRIP variants. All individuals had ID. Autistic features were observed in two. One individual showed myoclonic-atonic epilepsy. Neuroradiological features comprised periventricular nodular heterotopia and widening of subarachnoid spaces. Two frameshift variants in the more severely affected individuals, likely result in haploinsufficiency. The third missense variant lies in the conserved RRM 2 domain likely affecting RNA-binding. Our findings support the importance of RRM domains for SYNCRIP functionality and suggest genotype-phenotype correlations. Our study provides further evidence for a SYNCRIP-associated NDD characterized by ID and ASD sporadically accompanied by malformations of cortical development and myoclonic-atonic epilepsy. This article is protected by copyright. All rights reserved.