Below is an instruction from Human. Write a response.
    ### Instruction:
    Is Retinoblastoma inherited ?
    ### Response:
    Retinoblastoma occurs in heritable and nonheritable forms.
                    A child is thought to have the heritable form of retinoblastoma when one of the following is true:         - There is a family history of retinoblastoma.    - There is a certain mutation (change) in the RB1 gene.
    