The result: an embryo that is an almost perfect genetic copy of the skin cell donor. (discovermagazine.com)
The resulting lamb was, as expected, an exact genetic copy, or clone, of the sheep that provided the transferred nucleus, not of those that provided the egg. (scientificamerican.com)
Because the cells that give rise to sperm divide frequently — about 23 times a year — they are much more likely to accumulate genetic copying errors than the female precursor cells, oocytes, which divide only twice before becoming eggs. (discovermagazine.com)