Below is an instruction from Human. Write a response.
    ### Instruction:
    Is Mosaic trisomy 9 inherited ?
    ### Response:
    Is mosaic trisomy 9  inherited? Mosaic trisomy 9 is usually not inherited. It often occurs sporadically as a random event during the formation of the reproductive cells (egg and sperm) or as the fertilized egg divides. In rare cases, mosaic trisomy 9 may be inherited from a parent with a chromosomal rearrangement called a "pericentric inversion.
    