Cloning of mice to six generations.

摘要: Mice have been cloned by nuclear transfer into enucleated oocytes1,2,3, and here we describe the reiterative cloning of mice to four six generations in two independent lines. Successive showed no signs prematureageing, as judged gross behaviouralparameters, there was evidence shortening telomeres at ends chromosomes, normally an indicator cellular senescence — fact, these appeared increase slightly length. This is surprising, given that number mitotic divisions greatly exceeds sexually produced animals any deleterious effects might be expected amplified sequentially mice. Our results offer a new approach study organismal ageing.