Description
Telomeres shorten with each round of cell division, and the expression of telomerase serves to lengthen telomeres. In the absence of telomerase, telomeres shorten to the point of uncapping and causes defects in tissues with high turnover, including the intestinal epithelium. In mice lacking telomerase (e.g. mTR-/-), telomeres critically shorten after several generations of telomerase deficiency, with pronounced defects in their intestine.