Gene Mosaicism

Gene mosaicism is the occurrence of two different genotypes in a person which came from a single fertilized egg. This may be caused by uncharacteristic spontaneous cell division, gene or chromosomal mutation, viral infection, or random switching off of an X chromosome. This condition may affect any type of cell and my lead to various characteristics and syndromes such as having eyes with two different colors, Down Syndrome, Turner Syndrome, and Klinefelter Syndrome.