(Full text 1400 words, 4 minutes to read)
Among the rumors about "genetically modified poisoning", the most widely circulated and convincing "evidence" is the Frenchman Serralini's study that "genetically modified corn causes tumors in rats".
These rats ate herbicide-resistant genetically modified corn (denoted by GMO) and herbicide Roundup (denoted by R), and after a 2-year trial cycle, many rats developed tumors.
The visual impact of the huge tumors in the photographs that Serralini showed to the media was extremely strong.
This study is more than enough to fool ordinary people, but from a scientific point of view, it is a joke.
One scientist wrote in a review: "I can't believe how such a paper could have been published in SCI journals through editorial review!" ”。
【No control】
A cold sufferer who takes antibiotics is cured in 7 days, is the antibiotic working?
No, you see another cold patient who did not take antibiotics for 7 days and recovered.
This is where "control" is required.
If one group of mice eats genetically modified corn, another group of mice eats regular corn, eats genetically modified long tumors, and the other group does not grow tumors or has fewer tumors, then you can suspect that there is something wrong with the genetic modifications.
However, Serralini showed three groups of mice that either ate GMOs or ate herbicides, so why didn't he show mice that ate normal corn?
This has to start with the origin of the rat.
【Origin of laboratory animals】
Scientists once had a dream that laboratory animals would be carved out of a mold, so that the differences between individuals would be small and the experimental results would be easier to interpret.
After Mendel's pea experiments, scientists, guided by genetics, successfully bred the world's first ideal "laboratory animals."
At present, common experimental animals are divided into inbred lines, distant lines, hybrid lines, mutant lines and other categories, wistar rats and SD rats belong to the "distant lines".
【Why is it a rat】
Because it's big and white! Isn't that... The key is why it's white.
Wistar rats and SD rats are experimental animals commonly used in toxicological research.
Wistar rats originated from the Wistar Institute in the United States, SD rats are bred on the basis of Wistar, SD is the abbreviation of the farm name.
The reason why it is white is because of albinism.
Have you ever noticed that its eyes are red? This is also one of the symptoms of albinism.
In the same way, mice, white rabbits, great white whales, and bai suzhen are actually albinism patients.
【Pure blood, capitalized dirt】
The distant lineage, also known as the closed group, is obtained by a small group of rats who do not know the truth and mate behind closed doors for more than 15 generations.
In the end, this group of rats is basically distant relatives.
In contrast, inbred animals are capitalized.
They were obtained over 20 generations of sibling, father-daughter, mother-child incest, and all rats share a common ancestor.
Inbreeding leads to "genetic homozygoticity", and small individual differences are good for experimentation, but it is easy to get genetic diseases, and albinism is only one of them.
Hemophilia, which was once prevalent in european courts, was also caused by the pursuit of royal "purity of blood", and various purebred cats and dogs were often plagued by diseases.
(There are many famous historical figures in the following picture))
【The great white life is not long】
The life span of rats generally ranges from 1-3 years, and the physical fitness of rats used in experiments is not very good, and the average life expectancy is only about 2 years.
For example, in one study, after 2 years of Wistar rat feeding with normal feed, only about 61% of male rats survived, and male and female rats survived 57%.
In another substantially similar study, male Wistar rats had a 2-year survival rate of 56% and female rats with a 62% survival rate.
In one study of SD rats, after 2 years of normal feed feeding, male rats had a 55% survival rate and 52% for males and females.
That is to say, under normal circumstances, more than 40% of rats live for less than 2 years.
【Large white tumors】
There are many genetic diseases in rats, spontaneous tumors are one of them, and the site of the tumor is not fixed.
Although the probability of spontaneous tumors in Wistar rats and SD rats is relatively low among rats, it is only relatively low.
For example, Wistar rats are fed conventional feed for 2 years, and nearly 50% of male rats have tumors, and female rats have tumors of more than 60%.
In a similar study, 60 percent of male Wistar rats had tumors, while female rats had a tumor incidence of as high as 76 percent, and more than half of them had multiple tumors in different sites.
In one study of female SD rats, the incidence of breast tumors alone reached 46% over a 2-year cycle.
In another study, nearly 800 SD rats had a tumor incidence rate of 64% (84% for females and 44% for males), and on average, there were more than 2 tumors on average, and the most one had 9 tumors.
That is, under normal circumstances, at least half of the rats will grow tumors within 2 years.
Speaking of which, you probably get it.
If you have a group of rats that eat normal corn, you will find that these mice are almost dead after 2 years, and most of the people who are not dead also have tumors.
I believe that Serralini's experiment actually included a group of mice that ate normal corn.
However, after 2 years of breeding, this group of mice has died in pieces, and compared with other groups, it is impossible to explain that the GM is toxic.
That's why Serralini doesn't show rats that eat normal corn.
Because the study did not stand up to scrutiny, the journal eventually had to retract the paper.
In fact, there are many people who question GMOs, management omissions, scientist arrogance, and stains on GM companies, which are all points of attack.
But so far, there has not been a single question about the safety of GMOs.
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