Production of healthy cloned mice from bodies frozen at −20°C for 16 years

• DOI: 10.1073/pnas.0806166105
• Publication Date: 2008-11-04T02:36:52Z
• Authors: Sayaka Wakayama; Hiroshi Ohta; Takafusa Hikichi; Eiji Mizutani; Takamasa Iwaki; Osami Kanagawa; Teruhiko Wakayama
• Keywords: Cloning (programming); Mammoth

Cloning animals by nuclear transfer provides an opportunity to preserve endangered mammalian species. However, it has been suggested that the “resurrection” of frozen extinct species (such as woolly mammoth) is impracticable, no live cells are available, and genomic material remains inevitably degraded. Here we report production cloned mice from bodies kept at −20 °C for up 16 years without any cryoprotection. As all were ruptured after thawing, used a modified cloning method examined nuclei several organs use in attempts. Using brain donors, established embryonic stem cell lines embryos. Healthy then produced these transferred serial transfer. Thus, techniques could be “resurrect” or maintain valuable stocks tissues prolonged periods cryopreservation.