Below is an instruction from Human. Write a response.
    ### Instruction:
    Is Trisomy 18 inherited ?
    ### Response:
    Is trisomy 18 inherited? Most cases of trisomy 18 are not inherited and occur randomly due to errors in the formation of eggs or sperm. If an egg or sperm gains an extra copy of chromosome 18 during cell division and contributes to a pregnancy, the embryo will have an extra chromosome 18 (trisomy) in each cell of the body.
    