ARID1A and Hydrocephalus: In addition, variants were identified in the other 4 phenotype categories involving 4 genes, including 2 cases of L1CAM associated with Hydrocephalus Due To Congenital Stenosis Of Aqueduct Of Sylvius (307,000), PLAA associated with Neurodevelopmental Disorder With Progressive Microcephaly, Spasticity, and Brain Anomalies (617,527), PIEZO1 associated with Lymphedema, Hereditary, Iii (616,843), and ARID1A associated with Coffin-siris Syndrome 2 (614,607).