Rare Case with Pathogenic Variant in DHX16 Gene Causing Neuromuscular Disease and Oculomotor Anomalies

The DEAD/DExD/H-box RNA helicases are a group of RNA-binding proteins involved in the metabolism of mRNAs. They coordinate gene expression programs and play a role in cellular signaling, fate, and survival. We describe a case of a 36-year-old female with neuromuscular disease, sensorineural hearing loss, retinitis pigmentosa, and primary ovarian insufficiency harboring a heterozygous de novo missense pathogenic variant in the DEAH-box helicase 16 (DHX16) gene. This is the first case exhibiting a high intellectual level and the highest survival outcome so far. Eight previous cases of DHX16 disease-causing variant carriers have been described with common features, including muscle weakness with hypotonia, myopathy or peripheral neuropathy, sensorineural hearing loss, abnormal retinal findings, and infantile spasms or epilepsy. Increasing evidence associates RNA-binding proteins, including the DEAD/DExD/H-box helicase family genes, with neuropsychiatric or neurodevelopmental disorders. DHX16 genetic analysis should be considered early when diagnosing a child or young adult with muscular disease, severe hearing loss, and ocular anomalies.