PRRT2 and headache disorder: These disorders were shown to be caused by heterozygous variants in PRRT2. 187,193 In a review of 1,444 published cases with 70 distinct PRRT2 mutations, 42%, 39%, and 14% of affected individuals were diagnosed with SeLIE, PKD, and ICCA, respectively, with the remaining affected individuals suffering from various disorders, including seizures and headache disorders.193