Genome Variety: Humans a 'Mosaic of Cells with Different Genomes'

November 18, 2012 | Scientists at Yale School of Medicine have found that the human body is "made up of a mosaic of cells with different genomes." While studying skin cells derived from stem cells, researchers found genetic variation at the cellular level: skin cells displayed varying levels of copy number variations. The team used whole genome sequencing to compare the stem cells to the skin cells from which they originated--using the stem cells as a "magnifying glass" to look at the DNA. "In the skin, this mosaicism is extensive and at least 30 percent of skin cells harbor different deletion or duplication of DNA, each found in a small percentage of cells,” said Flora Vaccarino, lead author on the study. The study was published yesterday in Nature. Yale University News