Below is an instruction from Human. Write a response.
    ### Instruction:
    Is trisomy 13 inherited ?
    ### Response:
    Most cases of trisomy 13 are not inherited and result from random events during the formation of eggs and sperm in healthy parents. An error in cell division called nondisjunction results in a reproductive cell with an abnormal number of chromosomes. For example, an egg or sperm cell may gain an extra copy of chromosome 13.
    