Chromosomal abnormalities are associated with aging and cancer

Mosaicism, the type of structural abnormality in chromosomes that is described in these studies, results from a DNA alteration that is present in some of the body's cells but not in others. A person with mosaicism has a mixture of normal and mutated cells.

http://www.cancer.gov/newscenter/pressreleases/2012/mosaicismNCINHGRI