& nbsp;& nbsp;& nbsp; I've heard of surrogate mothers, but have you heard of surrogate fathers? This is not a myth& nbsp;& nbsp;& nbsp;& nbsp; From a common sense point of view, male animals have no womb and cannot complete the task of breeding new life
Different from the "surrogate mother", the "surrogate father" is just to cultivate more fine sperm& nbsp;& nbsp;& nbsp;& nbsp; This technical progress was published in the Journal of the National Academy of Sciences of the United States on September 14
It is the result of six years of cooperation between researchers from Washington State University, Utah State University, the University of Maryland and the Roslin Institute of the University of Edinburgh in the United Kingdom& nbsp;& nbsp;& nbsp;& nbsp; Animal embryos are bred into "surrogate fathers" & nbsp;& nbsp;& nbsp; Researchers from the Roslin Institute of Edinburgh University, which is famous for cloning the world's first mammal dolly sheep, cooperated with American scientists to knock out a gene related to male fertility - Nanos2 gene in animal embryos by using the gene editing tool crispr-cas9
These animal embryos will be bred into "surrogate fathers"
After transplanting the stem cells provided to help the animals (donors) into the testicles of the "surrogate fathers", the "surrogate fathers" began to produce sperm containing only the genetic material of the donor animals& nbsp;& nbsp;& nbsp;& nbsp; So, how does the gene editing technology operate in the process of cultivating "surrogate fathers"? "The gene editing tool crispr-cas9 was used to knock out the genes specific to male fertility in animal embryos, so that the male animal could not produce sperm and had no fertility
The researchers then transplanted spermatogonial stem cells from other breeding animals into the testes of gene editing animals, so that they could normally produce sperm
" Tang Bo, a doctor of molecular biology from China Agricultural University, said in an interview with science and technology daily& nbsp;& nbsp;& nbsp;& nbsp; Tangbo said that because the sperm produced by the male animals of gene editing does not belong to themselves, but belongs to other breeding animals, such animals of gene editing are called "surrogate fathers"
In contrast, embryo transfer and somatic cloning techniques require the use of "surrogate mothers" to produce offspring genetically belonging to other breeding animals& nbsp;& nbsp;& nbsp;& nbsp; It is worth noting that the sperm produced by the "surrogate father" only contains the genetic material of the donor animal
That is to say, the offspring of these sperm are the offspring of donor animals, and the role of "surrogate father" is to act as a sperm production machine and help the female complete pregnancy& nbsp;& nbsp;& nbsp;& nbsp; The researchers say the technology will accelerate the spread of traits needed by livestock and increase global food production
It will also enable breeders in remote areas to better obtain the excellent characteristics of excellent animals in other parts of the world, and enable goats and other animals that are difficult to use artificial insemination technology to obtain more accurate breeding
In addition, this technology also opens the door for the genetic protection of endangered species
The number of endangered species is decreasing, which limits their genetic diversity& nbsp;& nbsp;& nbsp;& nbsp; It can overcome the limitations of existing animal husbandry breeding technology & nbsp;& nbsp;& nbsp; For decades, scientists have been looking for a way to produce surrogate offspring to overcome the limitations of selective breeding and artificial insemination
In many cases, artificial insemination has strict requirements and can not be successfully applied to some animals, which hinders the progress of breeding better animal varieties& nbsp;& nbsp;& nbsp;& nbsp; "Surrogate father" technology can solve these problems, because this technology transfers the genetic material of the donor through normal reproduction in a natural way, which enables ranchers and herdsmen to allow the farmed animals to interact normally in the pasture or field
Because the stem cells of differentiated sperm can be transported to different places by freezing, helpers and surrogates can even "transfer genetic material" across the space& nbsp;& nbsp;& nbsp;& nbsp; Tang Bo introduced that by using this "surrogate father" technology, scientists can make breeding animals with low performance produce a large number of sperm with good performance
Combined with artificial insemination technology, they can quickly breed a large number of excellent herds, greatly speed up the process of animal breeding improvement, and improve the production efficiency of animal products and feed conversion rate& nbsp;& nbsp;& nbsp;& nbsp; For example, Tang Bo said that after finding a better breeding boar in animal husbandry production, the semen of the breeding boar will generally be used to breed as many sows as possible
However, the semen production capacity of a breeding boar is very limited, and it will take several years to adopt conventional techniques to cultivate this kind of excellent breeding boar
If the "surrogate father" technology is adopted, more "surrogate fathers" can be used to produce a large number of fine semen in a short time& nbsp;& nbsp;& nbsp;& nbsp; Why can't the previous artificial animal breeding technology meet the breeding needs of animal husbandry? Tang Bo introduced that artificial breeding technology includes artificial insemination, embryo transfer and other technologies
Artificial insemination is to use the semen of good male animals to breed as many female animals as possible, so as to give full play to the genetic advantages of good male animals
However, good male animals, especially better male animals, are often rare, which limits the use of artificial insemination technology& nbsp;& nbsp;& nbsp;& nbsp; "Embryo transfer technology is to transfer embryos prepared in vitro or embryos obtained by superovulation to other female animals with low performance, and breed more offspring of excellent female animals in a short time, so as to give full play to the genetic advantages of excellent female animals
If the number of excellent female animals is small, embryo transfer technology can not play a role
" Said Tangbo
