Genetic Determinism: What It Is And What It Implies In Science
In the last hundred years, important discoveries have been made in the field of biology that have allowed us to understand how our physical and psychological characteristics are more similar to those of our parents than to those of other people.
Genetics has been expanding its field of knowledge, especially since Mendel did his first experiments on how traits were inherited and also when Rosalind Franklin and company discovered that DNA was the molecule that contained genes.
Starting from the idea that we are what we have inherited, there were many, both scientists and politicians, who defended the idea that our behavior and physical characteristics depend entirely on our genes. This is what has been called genetic determinism It was argued that there was no possible way to change these characteristics, because genes were above practically any environmental factor. This was what ultimately led to some of the worst episodes in modern history.
Let’s take a closer look at what the belief behind genetic determinism is and how it has been applied throughout the 21st century.
Genetic determinism, also called biological determinism, is the set of beliefs whose common idea is the defense that human behavior depends for the most part on the genes that have been inherited This opinion also defends the idea that the environment hardly has any influence on a person’s behavior or way of being.
Thus, if a person is the daughter of tall and intelligent parents, by inheriting the genes behind these characteristics they will undoubtedly present them. At the same time, in the case of having parents with some type of mental illness or disorder, there will be a risk of inheriting the genes that may be behind these illnesses and, according to genetic determinism, these problems will inevitably manifest. .
Genetic determinists considered that genetics was what fully or mostly explained how people are and that environmental and social factors barely influence the way humans are. This type of thinking came to defend the unnecessary need to educate or carry out therapeutic processes because, if the person was less intelligent or suffered from a disorder because there was a certain tendency towards it in their family, why fight against genetics? If it has to manifest, it will manifest.
By reducing everything that the human being is to simple genetic explanations, the environment in which the most advantaged and the most disadvantaged people had developed was often ignored. A tall person who has lived in an environment in which there has not been any type of lack of food is not the same as a shorter person who has suffered malnutrition. This example, although simple, serves as an explanation that, sometimes, the environment can be much more determining than genetics itself.
Genetic determinism and how it has influenced modern history
These are some examples of the way in which genetic determinism has been reflected in theories and ways of understanding the world in general.
August Weismann and the germ plasm
In 1892, the Austrian biologist August Weismann proposed the idea that multicellular organisms, such as humans and other animals, had two types of cells: somatic cells and germ cells. Somatic cells are responsible for the basic functions of the body, such as metabolism, while germ cells are responsible for transmitting hereditary information.
This biologist was the first to propose the existence of a substance in which hereditary characteristics were found and that was behind how a living being was genetically configured: the germ plasm.
The primitive idea of ​​germ plasm was the precursor to what we know today as deoxyribonucleic acid or DNA. The idea behind the germ plasma was that it contained the genes, which controlled what the organism was like.
Weismann argued that the material present in the germ cells could not be modified during the life of the organism This idea clashed with the idea of ​​Lamarkism, which held that events that occurred in the life of an individual that entailed changes for the organism would also be transmitted to the subsequent generation.
Genetic reductionism and social Darwinism
As time went by, August Weismann’s own ideas mixed with the thoughts on evolution expressed by Charles Darwin in The Origin of Species (1859), the idea of ​​social Darwinism emerged, defended by Darwin’s own cousin, Francis Galton.
It should be said that Darwin never intended for his ideas about evolution to be distorted and misinterpreted as did those who used Darwinian evolutionary principles when explaining the characteristics of the population.
The idea behind social Darwinism is genetic reductionism, which consists of defending that aspects as complex as personality or suffering from a certain type of psychological disorder are caused by just one or two genes. According to this view, A person who has inherited just one gene considered poorly adaptive will manifest the unwanted behavior no matter what
Starting from genetic reductionism, social Darwinism defended that the differences between races, genders, ethnic groups and social classes were undoubtedly due to having inherited bad genes and, therefore, applying discriminatory measures taking this into account was totally justifiable.
As a consequence of these beliefs, One of the first measures that defended social Darwinism were the eugenic laws applied in various places in Europe and North America starting in the 1920s and 1930s.
The eugenics movement maintained that negative traits, both physical, such as having motor disabilities, and psychological, such as suffering from schizophrenia or low intellectual performance, had a genetic basis and, to prevent their spread, those who manifested them should be prevented from reproducing. .
If people with bad genes were prevented from having offspring, these genes would not be passed on to the next generation, thus exterminating maladaptive characteristics. In this way, thousands of people in the United States were sterilized. These same eugenic laws were taken to the extreme in Nazi Germany applied in the form of mass extermination of people who, according to the prevailing racism, were inferior to the Aryan race: Jews, Poles, gypsies, as well as non-ethnic groups but considered maladjusted, such as homosexuals and anti-fascist people.
Not everything is genetics, not everything is environment: epigenetics
In recent years, humans have tried to find out how many genes they have. Until relatively recently, it was believed that human beings must have around 100,000 genes. The reason for this was that approximately the same number of proteins were found in the human species and, taking into account the scientific principle (now rejected) that a specific protein is produced for each gene, there must have been that number of genes in our species.
When the Human Genome Project revealed in 2003 that the human species actually only had a total of 30,000 genes, scientists were somewhat confused. Human beings barely have more genes than mice or house flies This finding was surprising because it was somewhat shocking to discover that a species as apparently complex as ours had a relatively low number of genes.
From this the idea was raised that it really wasn’t all genes. That there was something else that influenced the production of such a high amount of proteins, about 100,000, while there were so few genes, barely 30,000.
It is true that a person has a specific genetic configuration, the result of having inherited the genes of his biological father and mother. However, Whether these genes manifest or not may depend on certain environmental and even social factors The genotype of each person is that genetic configuration, but the phenotype is what actually manifests itself.
The gene-environment interaction has been called epigenetics and it is an aspect that has been gaining a lot of importance in recent years, especially in the field of health. Being able to influence what the person has genetically inherited apparently was not as impossible as was believed.
This finding completely contradicts the defenders of genetic determinism because, although they are right that the genes will continue to be in each and every one of the cells of an individual, The environment influences whether or not they will be activated and cause the person to behave in a certain way or suffer from a specific disease
A demonstration of this has been the discovery of the phenomenon of methylation, in which, either by having a specific type of diet, or by living in an environment in which the air is cleaner or more polluted, certain genes They are modified by incorporating a methyl group, without the need for genetic engineering to be carried out.
Thus, genetic material makes us have a tendency to manifest a specific type of cancer, have a particular type of personality or be physically slim, to give a few examples, but it does not limit you to being that. Between 10 and 15% of human diseases are hereditary, in the rest it is possible to modulate their effects by carrying out healthy habits.
It could be said that, today, in the field of hereditary and genomic science, the idea is defended that half of how we are is determined by the 25,000 genes that each of us possess, while the other half is determined by our social, dietary and climatic environment.
