Congenital cranial dysinnervation disorders (CCDDs) are a heterogeneous group of neurodevelopmental phenotypes caused by a primary disturbance of innervation due to deficient, absent, or misguided cranial nerves. CCDD with absent corneal reflex and developmental delay (CCDDRD) caused by mutations in NAUROG1 has been reported. NEUROG1 encodes Ngn1 which is a basic helix-loop-helix transcription factor essential for the formation of the proximal cranial sensory ganglia for cranial nerves V and VIII.
