Below is an instruction from Human. Write a response.
    ### Instruction:
    Is retinoblastoma inherited ?
    ### Response:
    Researchers estimate that 40 percent of all retinoblastomas are germinal, which means that RB1 mutations occur in all of the body's cells, including reproductive cells (sperm or eggs). People with germinal retinoblastoma may have a family history of the disease, and they are at risk of passing on the mutated RB1 gene to the next generation.
    