Monarch Disease Ontology identifier MONDO_0018160 (hereditary retinoblastoma) is an autosomal dominant disorder caused by pathogenic variants in the RB1 gene, characterized by an increased risk of retinoblastoma in early childhood. Individuals with hereditary retinoblastoma also have an increased risk of developing secondary cancers, such as osteosarcoma, melanoma and carcinomas in childhood and adulthood. Also known as: RB1, RB1-related retinoblastoma predisposition, familial retinoblastoma, retinoblastoma, autosomal dominant, somatic mutation, retinoblastoma, trilateral, autosomal dominant, somatic mutation.