The fantasies of perfecting human beings through genetics have recently been revived with the announcement of the Chinese scientist who claims to have created the first "CRISPR babies," named after the technique used to modify the DNA of embryos.
While important ethical and normative dilemmas are at stake, fears that this technology will lead us to a dystopian world like the one described in the movie "Gattaca are unfounded. In fact, if the film were made again today, it would probably be rather, a story about the government prescribing the use of probiotics and healthy eating.
Eugenics is based on the idea that humanity can be perfected with genetic manipulation and throughout history there have been different eugenic policies that imposed restrictions on marriage and immigration, justified slavery and forced sterilization and even led us to the Holocaust.
As a research doctor specializing in allergies I started to be interested in eugenics not in relation to a person's skin color, but with skin rashes. The most prominent researchers in the field of eczema were convinced that most cases are determined by fixed genetic sequences, which is true on many occasions. However, like previous studies on intelligence and criminal behavior, research on eczema genetics has been well below what the fifteenth-century techniques had predicted.
In Babies and more Intestinal flora is so important for health that it is already performed until stool transplantsIt is true that the general fascination on this subject is understandable. There are more and more pseudoscientific statements on television about how your DNA can reveal, for example, that you have 12.4 percent Italian, 3.1 percent Neanderthal and 1/512 American Indian. Spoiler: can't. There are many m = top "> magazines, podcasts and renowned newspapers that have driven the discredited claim that intelligence is marked by our genetic code.
Actually, genetic studies that were supposed to explain at least 80 percent of being a genius have only explained 5 percent, which means that your genes, at best, have less impact on your results. An intelligence test that a good night's sleep. However, contemporary misunderstandings about how complex traits are transmitted not only causes our society to be filled with charlatans and racists, but this type of ignorance causes us to put aside good opportunities to improve our health and how to treat diseases.
Where do ideas like the 'intelligence gene' come from?
Most of the ideas about "genes that define" complex traits come from studies in twins who assumed that twins and twins were only differentiated by the amount of DNA shared. But the researchers did not realize, or voluntarily ignored, that their environment also has a lot of influence in the case of identical twins. Because identical twins are more likely to dress alike and be confused with each other, they rather form a shared identity.
Therefore, identical twins are more likely to share the same hobbies, eat the same foods and have the same social circles as the twins. The most recent research shows that these differences are more psychological than biological. In addition, since identical twins share the same amniotic sac in the uterus, their environmental exposures are also more similar at the biological level than in the case of twins. That is why researchers who claim that the data from twin studies represent what happens in genetics are, at best, poorly informed.
In Babies and more A study reveals that the feeding of babies influences the metabolism of their intestinal bacteria What is the modern version of hereditary features?
Although it seems contradictory, the fact that a change can worsen the function of a gene does not mean that a different change can improve it. When scientists say that a gene "contributes to intelligence" they refer to situations in which mutations in the gene cause a loss of intelligence or a delay in cognitive development. They are not implying that a special version of the gene can guarantee a university degree.
The improvement of gene functions is usually achieved through epigenetic modifications: chemical indicators that adhere to DNA but do not alter the genetic code. If genes were words, phrases and paragraphs, then epigenetics would be cadence, emphasis and diction. This is like the difference between a Hamlet played by Gilbert Gottfried or Benedict Cumberbatch. Although epigenetic changes can be transmitted from parents to children, they can also be altered by stress, diet, environment and behavior. Thus, I believe that the modification of the environment, and not CRISPR technology, would be necessary to improve the vast majority of genetic functions.
Another way to inherit certain traits
There is a factor that influences hereditary traits and to which more attention has been given in recent times: the microbiome. This term designates all microorganisms (bacteria, fungi and viruses) that coexist peacefully in our bodies.
From a genetic point of view, there are probably a hundred times more microbial genes in your body than human genes and modern science suggests that the microbiome may be directly involved in diseases ranging from autism to obesity. Microbial influence can be transmitted from mother to child during and possibly before birth, but remains partially susceptible to diet and the environment in adulthood.
It is known that intestinal microbes play a role in mental health.The microbiome can even influence your epigenetics. Science has just begun to harness the potential of microbial treatments for diseases. Similar to our experimental treatment to combat eczema, live bacteria therapies are being developed to treat food allergies, depression and anxiety, heart disease and certain types of cancer. As scientists discover which strains of microbes are the most effective, these treatments are expected to become even more potent.
Let's put it as follows: The current president of the US and the former president share 99.9 percent of his genetic sequence, despite being only slightly more than 0.1 percent different. As such, modern scientists are not afraid of ideas based on eugenics because they are controversial; but they discard them because both "Gattaca" and The Curve of the Bell are films that for genetics have the same importance that Flat Earth can have for astrophysics.
Science has just begun to harness the potential of microbial treatments for diseases.Although a gene therapy carried out correctly may be a real hope of curing rare genetic diseases, its limitations do not reach science fiction. For example, feeding a specific type of bacteria in mice significantly improved their memory, while genomics could not find any gene that could do the same. Those obsessed with personal lineage and neo-eugenists may deny the fact that people are more a product of their experiences than of their genetic heritage, but perhaps their mothers simply did not breastfeed them long enough.
Author: Ian Myles. Chief, Epithelial Therapeutics Unit, National Institute of Allergy and Infectious Diseases
This article has originally been published in The Conversation. You can read the original article here.
Translated by Silvestre Urbón
