Phosphofurin Acidic Cluster Sorting Protein 1 Syndrome: Insights Gained on the Multisystem Involvement Reviewing Encoded Protein Interactions?

Mutations in PACS1 cause moderate-to-severe intellectual disability. Very few cases of PACS1 neurodevelopment disorder have been described in the literature that were identified using whole exome sequencing (WES). We report a case of de novo PACS1 mutation identified through WES after an initial workup for mucopolysaccharidosis. Through this case, we wish to emphasize that most important clinical clue in the facial gestalt is a downturned angle of mouth, thin lips, and wide mouth, giving characteristic wavy appearance of face that can distinguish these cases and can prevent unnecessary workup for the patients.