Ying bred a new type of transgenic cloned pig

Introduction: British ppl medical company, which once participated in the cloning of Dolly lamb, announced Tuesday that its researchers had recently bred five new transgenic cloned pigs, and one gene in them had been "shut down" This is another important progress in the field of xenotransplantation According to a press release released by ppl, the five piglets were bred by researchers from the company's Virginia based subsidiary They were all female and were born on December 25, 2001 DNA tests showed that one of the two alpha-1 (3-galactosyltransferase) (GT) genes in their bodies was in the "off" state Me3 researchers say the GT gene controls the production of an enzyme that makes a carbohydrate on the surface of pig cells When pig organs or cells are transplanted to the human body, the human immune system can recognize the sugar, which produces a strong rejection reaction, and attacks the transplanted organs or cells as foreign objects This is the main reason why pig organs can not be used in human transplantation If we find a way to inhibit the gene, it is possible to use transgenic cloned pigs to "produce" organs suitable for transplantation Me3 ppl Co., Ltd has cooperated with Roslin Research Institute in the UK to produce cloned sheep Dolly by nuclear transfer technology Since then, the company has been working on the same technology to produce genetically modified cloned pigs for transplantation In March 2000, ppl company announced to breed the first batch of cloned pigs in the world, and in April 2001, it also announced to clone the first batch of transgenic pigs with exogenous genes in vivo This time, a cloned pig with GT gene turned off has been successfully bred, which indicates that the goal of xenotransplantation is getting closer and closer Me3 due to the lack of transplantable organs, many patients in urgent need of kidney replacement, liver or heart cannot be treated in time Therefore, the research on xenotransplantation of animal organ to human has been paid more attention Pigs are easy to reproduce, and their organs are close to human organs in size and function, so they are regarded as an ideal source of alternative organs Me3 ppl scientists expect that the first application of transgenic cloned pigs in medicine will be to produce insulin producing islet cells for the treatment of diabetes, and clinical trials may start as early as four years Me3