Eye manifestations in the NSUN2 intellectual disability syndrome

The NSUN2-intellectual disability syndrome is a rare disorder of the cellular transcriptome that prevents proper t-RNA splicing. This disorder interrupts cellular function and leads to an accumulation of RNA fragments, producing a constellation of symptoms including dysmorphic facies, hypotonia, microcephaly, and short stature. Eye manifestations have been reported but not well characterized. Our study presents a new case involving a 4-year-old boy with novel NSUN2 variants and clinical features consistent with the syndrome. In addition, through a systemic review, we discuss the 24 previously reported cases of the syndrome with an emphasis on the eye and ocular adnexa clinical features.