Can the trick of getting close to breeding and removing harmful genes to save endangered animals?

Can this trick of getting close to breeding and removing harmful genes to save endangered animals?

Can the trick of breeding close to breeding and removing harmful genes save endangered animals? Can this trick of breeding close to breeding and removing harmful genes save endangered animals

Inbreeding is conducive to the continuation of unique genes.
This is because inbreeding will greatly increase the probability that the two copies of the gene in the offspring will be the same.
If the same gene is pathogenic, it will cause genetic diseases
.

Inbreeding is conducive to the continuation of unique genes.
This is because inbreeding will greatly increase the probability that the two copies of the gene in the offspring will be the same.
If the same gene is pathogenic, it will cause genetic diseases
.

—— Zhao Shaowei, Distinguished Researcher of the Department of Genetics and Cell Biology, School of Life Sciences, Nankai University

—— Zhao Shaowei, Distinguished Researcher of the Department of Genetics and Cell Biology, School of Life Sciences, Nankai University

◎Reporter Chen Xi

Scientists have always believed that inbreeding can cause various birth defects
.

This phenomenon is widespread in species with sexual reproduction, and the evolutionary significance of sexual reproduction lies in increasing the diversity of species through the reorganization of the genetic information (genes) of individual males and females

However, a paper recently published in "Cell Genomics" found a new case of inbreeding on genes: When Swedish and New Zealand researchers sequenced the genome of the kakapo on Stewart Island, New Zealand, they found that they had experienced 1 After thousands of years of isolation and inbreeding on isolated islands, the number of harmful gene mutations in the kakapo was less than that on the main island
.

This case also proves that harmful gene mutations can be eliminated during inbreeding
.

Can the existence of this removal mechanism really bring new life to endangered species?

Increasing incidence of inbreeding genetic diseases

Increasing incidence of inbreeding genetic diseases

"From the perspective of population genetics, non-inbreeding can maintain the genetic diversity of species to the greatest extent, which is conducive to species coping with complex and changeable environments
.

" Zhao Shaowei, a distinguished researcher in the Department of Genetics and Cell Biology, School of Life Sciences, Nankai University, explained The principle of gene combination for this phenomenon is very simple.

Most genetic diseases are caused by recessive gene mutations, and only when the gene mutation is homozygous, the individual will develop the disease
.

In the heterozygous state, the individual is normal

The well-known "royal disease" hemophilia is a recessive genetic disease.
Previously, European royal families intermarried close relatives in order to maintain a pure bloodline, resulting in a high incidence of hemophilia among royal family members
.

In addition, albinism and red-green blindness are relatively common recessive genetic diseases

"This is also the reason why almost all countries in the world prohibit the marriage of close relatives.
This principle is also the same in other sexually reproductive species
.

" Zhao Shaowei said that two individuals with a relatively distant relationship mate, and their offspring are genetically recombined.

But sometimes, in order to allow horses, dogs and other pets to retain their unique genes to the greatest extent, people will also allow them to breed in close relatives to ensure the purity of their bloodlines
.

"Inbreeding is conducive to the continuation of unique genes.
This is because inbreeding will greatly increase the probability that the two copies of the gene in the offspring will be the same.
If the same gene is pathogenic, it will lead to genetic diseases; if the same gene It does not cause disease, but causes certain unique traits, such as bigger and stronger horses, smoother and beautiful manes, and some dogs looking more cute
.

" Zhao Shaowei introduced that through inbreeding, especially purebreds Mating between them is more able to continue this unique gene and its determined traits

Long-term inbreeding harmful mutations are eliminated

Long-term inbreeding harmful mutations are eliminated

The latest research mentioned above is aimed at a special kind of parrots called kakapo
.

They are very heavy and can't fly

Research data shows that the surviving kakapo populations on Stewart Island have been isolated for about 10,000 years, and they carry fewer harmful gene mutations than their counterparts on the main island
.
This also confirms that during this period, harmful gene mutations were eliminated by a natural selection process called elimination
.

Scientific theory believes that in small populations, harmful mutations may accumulate, leading to an increased risk of extinction
.
However, harmful gene mutations exposed through inbreeding may also be eliminated through natural selection.
This process is called elimination
.

Zhao Shaowei explained that in fact, the process of elimination is that during the long inbreeding process of kakapo, harmful gene mutations have a higher probability of being homozygous among individuals in the population, which in turn leads to individual illness and death being eliminated by natural selection.
These harmful gene mutations follow.
It disappeared
.

"Inbreeding will greatly increase the probability that these harmful gene mutations are homozygous in the same individual, that is, the probability that both copies of the same individual's genes are bad will increase, thereby promoting this elimination process
.
" Zhao Shaowei said
.

It is more reliable to protect endangered species and increase species diversity

It is more reliable to protect endangered species and increase species diversity

Regarding the results of this study, the researchers seem to see new hope for the continuation of the protection of the species in a critically endangered state.
They believe that over time, a large number of genetic defects have disappeared, and a high degree of inbreeding may not necessarily mean that the species is doomed.
To be extinct
.

Zhao Shaowei did not agree with this very much.
He said: “On the whole, inbreeding is not good for the continuation of a sexually reproductive species
.
Because it will increase the probability of homozygous pathogenic genes in individuals, and furthermore In addition to reducing the population size, it will also greatly reduce the genetic diversity of species, which is not conducive to species coping with a complex and changeable environment
.
"

As the population of endangered species decreases and the probability of inbreeding increases, more individuals will be eliminated due to genetic diseases and physical defects
.
For example, because of people’s pursuit of purebred pets, people will make pets inbreed to make their bloodlines more and more pure, but animals will also greatly increase the probability of homozygous disease-causing genes due to inbreeding.
Some famous purebred dogs There are a variety of genetic diseases, which make it more "gold and precious" to breed, and such reproduction is accompanied by a low survival rate and a high elimination rate
.

"Using this method of elimination to eliminate harmful gene mutations, the most likely result should be that the population size drops below the minimum threshold number, which will lead to the extinction of the entire species
.
" Zhao Shaowei believes that the protection of endangered animals still needs to increase the population size.
It is more reliable to allow individuals with relatively distant physical and genetic relationships to mate and reproduce offspring, avoid inbreeding, increase species diversity and protect the population
.

However, Zhao Shaowei also said that this research also has certain positive significance for the protection of endangered animals and the continuation of species.
After all, it gives an example of inbreeding and the elimination of harmful mutations.
It can be said to be one of the advantages of inbreeding.

.
These kakapo, which have been violently eliminated, should be healthier.
Using them to mate with the same species on the main island may be helpful to restore the population
.