Li Ning's scientific research achievements

The field of functional gene mining and molecular breeding of livestock and poultry. (1) It was confirmed that the intron of porcine follicle-stimulating hormone β subunit gene contained 292bp, palindrome structure and 3 1 poly(A) transposon. This achievement is one of the three patents on animal bedding properties awarded by the US Patent Office in the world. A method suitable for large-scale gene detection was developed. His achievement won the second prize of the National Technological Invention Award in 2003 (the first person to complete it). (2) In cooperation with BGI scientists, the construction of "Genetic Variation Map of Chicken Genome SNP" was completed, and it was found that the density of single nucleotide base mutation sites in chicken was 5 mutation sites per thousand bases; There are great differences in economic characters between domestic chickens and pheasants. This achievement was published in Nature (65438+February 9, 2004). DNA fingerprinting, microsatellite markers and other technologies are applied to the diversity assessment of animal genetic resources in China. Using restriction endonuclease fragment length polymorphism technology, the DNA molecular markers of leukemia resistance were developed, and the DNA markers and detection methods linked to sex-linked fast and slow feather sites were developed. The molecular genetic basis of chicken sex-linked dwarf gene and many other achievements were expounded.

The field of bovine somatic cell cloning and transgenic somatic cell cloning. ① Somatic cell cloning technology of high-quality dairy cows. The success rate of cloned blastocysts, the conception rate of cows and the calving rate all reached the advanced level in the world. Somatic cloned cattle were successfully produced by using frozen oocytes as nuclear transfer recipients for the first time. Frozen cloned embryos were successfully transferred. ② Somatic cell cloning technology of Holstein bull. Obtaining healthy cloned individuals opens up a new way for species protection and reproduction; The blastocyst development rate of cloned bull is 48.3%, the pregnancy rate of frozen embryo transfer is 33.3%, and the birth rate is 20%, which generally exceeds the international similar research level. The molecular mechanism of high mortality of cloned cattle has been partially clarified and published in Reproductive Biology. A relatively complete and effective production technology platform for cloned cattle with transgenic somatic cells has been established, and a number of innovative achievements have been achieved. The success rate of transgenic screening by double markers was 90% ~ 100%, and the pregnancy rate of transgenic cloned cattle was 28%. Somatic cloned cattle with three foreign genes, such as fucosyltransferase, were successfully cultivated. Up to now, 3 1 transgenic cloned cattle with various genes of human milk have been produced, of which 23 are alive, which is one of the largest transgenic cloned cattle populations in the world.