Benign infantile convulsions (IC) and subsequent paroxysmal kinesigenic dyskinesia (PKD) in a patient with 16p11.2 microdeletion syndrome.

Paroxysmal kinesigenic dyskinesia with infantile convulsions (PKD/IC) is caused by mutations in the gene PRRT2 located in 16p11.2. A deletion syndrome 16p11.2 is well established and is characterized by intellectual disability, speech delay, and autism. PKD/IC, however, is extremely rare in this syndrome. We describe a case of PKD/IC and 16p11.2 deletion syndrome and discuss modifiers of PRRT2 activity to explain the rare concurrence of both syndromes.