Human first bred "gene knockout" cloned pig

Introduction: with the active participation of Chinese scholars studying in the United States, a study started in 1998 at the University of Missouri in the United States finally came to fruition: scientists have used gene knockout technology for the first time in the world to cultivate cloned pigs without human immune rejection genes The scientific community generally believes that this is a key step towards xenotransplantation This paper, written by Dr Lai Liangxue, a Chinese scholar studying in the United States, was recently published in the authoritative journal Science "In the past, xenotransplantation was just an idea, now we can use the cloned pig organs to test the feasibility of this idea," Lai Liangxue said in reply to an email from Xinhua news agency Professor Chen Dayuan, who is carrying out the research on cloning giant panda, said after hearing the news: "the significance of this research is very great Pig's tissues are relatively close to human beings If this rejection gene is knocked out, organ transplantation will not be solved?" The shortage of transplantable human organs has always been a problem in the medical field Every year, more than 63000 patients in the United States need to receive organ transplantation, while only about 20000 organs are available for transplantation To solve this problem, the scientists turned their attention to pigs Pig organs are similar to human organs in size, structure and function, which has always been the main research goal of xenotransplantation But there is a kind of galactosyltransferase on the surface of pig cells, which will lead to strong rejection of human immune system In theory, gene knockout can inhibit the activity of this substance, combined with cloning technology, it should be able to mass produce pig organs suitable for human transplantation, weaken or eliminate the rejection reaction Therefore, the success of gene knockout cloned pig breeding has attracted much attention As the main finisher and organizer, Dr Lai Liangxue, together with other researchers in the laboratory of Professor palladze of the center for animal science of the University of Missouri, used gene knockout technology to produce seven cloned pigs without "rejection gene" in September and October 2001 In addition to four dead pigs, the surviving pigs are now in good condition of growth and normal weight growth According to Lai Liangxue, the current cloned pigs knock out the "exclusion gene" in two chromosomes, and the gene still exists in the other chromosome, so in order to speed up the research process, the laboratory will carry out a second round of gene knockout experiment If successful, it is possible to obtain cloned pigs for xenotransplantation within one year Lai Liangxue, 39, who is in charge of this project, graduated from the Department of veterinary medicine of Sichuan Animal Husbandry University in 1984 He has obtained master's degree and doctor's degree in Changchun veterinary University and Northeast Agricultural University He has successively engaged in the research of rabbit embryo cell separation and transgenic mammary gland bioreactor In October 1998, he went to the United States to do postdoctoral work.