Posted by on July 27, 2020 7:11 am
Categories: Uncategorized

scientists first applied CRISPR bred to be prolific of male offspring of cattle:male ratio can reach 75%!

in recent years, gene editing CRISPR has been used to edit a variety of animals for various purposes, for example: the pig is designed to be resistant to swine flu or body fat lower Pig, The Lizard is designed to albinism, the mosquito is designed to not spread diseases mosquitoes, bred the hair grow longer sheep…… Latest news shows, the use of CRISPR technology to transformation the more likely to produce male offspring of cattle, have also become a reality.

UC Davis scientists have successfully bred a cow named Cosmo(Cosmo)a small bull. This little bull is not simple-it is as embryos for genome editing, so it will be able to breeding more male offspring. It produces male offspring are more likely to reach 75 percent!

the results of the study to local time, 7 on 23 May published in the American Society of animal science American Society of Animal Science meeting poster on.

the use of CRISPR gene editing technology, researchers can for the genome to be targeted cutting or inserting useful genes, which is called gene knock-in. While the latest experiments, the scientists succeeded in causing male development, the SRY gene implantation bovine embryos. This is the first time in cattle by embryo-mediated genome editing technology, the large sequences of DNA for targeted gene knock-in.

University of California, Davis Animal Science Department of animal geneticist Alison Van Eenennaam says:“we expect that both Cosmo offspring whether inherited Y chromosome, the inheritance of the SRY gene of the offspring will look like a male.”

more bull and more beef

Van Eenennaam said that the production of more bull part of the motivation is–the Bulls can feed into their own efficiency increased by 15%, while the cow is often difficult to do this. In addition, they grow after the body weight often than a cow much higher.

it to the environment also benefits, because the production of the same amount of beef now requires less cattle now. Ranchers can produce some of the female bovine as a substitute, and to provide the market with a higher proportion of male cattle.” Animal science post-doctoral fellow Joyce Owens(Joey Owen)said. He and Van-El within Arnhem(Van Eenennaam)co-lead this project.

a off grueling Test tour

scientists have the SRY gene insertion number is 17, the bovine chromosomes, which ensures that the genetic elements can be predictive of function, and does not destroy adjacent gene expression or regulation.

the ideal case, the SRY gene will be inserted into the X chromosome-and as a result, the Cosmo will produce 100%male offspring. But the team cannot do this, try to knock the X chromosome of the gene after the failure, the scientists chose to chromosome 17, which will lead to a bull produced only male offspring. Small bull Cosmo’s offspring, is expected to male ratio of 75%–the normal case is 50% XY, while the other 25%is Genetic the SRY gene XX.

“the researchers spent two and a half years to develop the genes inserted into the developing embryo of the method, and spent two years successfully to achieve pregnancy.” But in the year 2020, 4 month, only 110 pounds a healthy bull calf was born, this is a breakthrough!

Van Eenennaam said, This is just research at the start. Cosmo will be in a year after reaching sexual maturity, he will be bred to study the inheritance of chromosome 17 on the SRY gene is sufficient to in XX embryos triggers male development path, and cause future generations to grow and looks like a male.

since the United States���Food and Drug Administration the animal gene editing as a drug to regulatory, Cosmo and his offspring will not enter the food supply in the field. It is more of in order to test this particular gene editing process is in accordance with expectations as a work.

this project stems from the Alison Van Eenennaam leadership of one called“Just for boys”for Boys Only item. The team of other researchers including a UC Davis Animal Science Department of the James Murray James Murray and Pablo Ross Pablo Ross, and Sadie·Hennig(Sadie Hennig and Jason forest Jason Lin, as well as the UC Davis Veterinary Hospital Brett·Mcnabb(Bret McNabb and column default·Manso(Tamer Mansour)。

the project by the United States Department of Agriculture, University of California, Davis; California Agricultural Experiment Station and the United States Department of Agriculture NIFA national needs graduate fellowships grants.

compile/proactive economist APP Information Group

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Published at Mon, 27 Jul 2020 11:10:55 +0000