Mutations of BAP1, PTEN, and PBRM1 are predominantly found in iCCA, whereas mutations of TP53, ARID1A, CDKN2A, CHK1/2, ATM, ATR, and BRCA occur in all CCA subtypes [103,104,105]. The gene discussed is CDKN2A; the disease is infantile convulsions and choreoathetosis.