Cytogenetic Instability of Stem Cells

DIVIDING CELLS ARE subject to errors during cell division that can result in abnormal chromosome patterns. Cytogenetics, which involves the study of abnormal chromosomes, has shown that human and mouse embryonic stem (ES) cells from laboratories throughout the world tend to show the same chromosome aberrations. The most frequent change in human ES cells involves gain of chromosomes 12 or 17, both of which are associated with cancer, whereas mouse embryonic stem cells tend to acquire extra copies of chromosomes 8 or 11. There is no way to distinguish embryonic stem cells with abnormal chromosomes from normal stem cells without genetic testing, as both express the same proteins and typical stem cell markers, and the presence of chromosome changes does not affect the ability of ...