ACVR1 and craniopharyngioma: The OMIM database contains only 3 entries containing the keywords “craniopharyngioma/+craniopharyngioma.” Among them, the ACVR1 gene was identified, which is highly impractical to detect using in situ hybridization due to the specificity of the mutation, characterized by the replacement of arginine with histidine at codon 20 (OMIM 102576).