The big bluff of the epigenetics gurus

Whenever scientific knowledge advances, introducing new concepts and new terms to describe them, it may happen that some of these take on a life of their own, so to speak, abandoning the semantic field in which they make sense, for overflowing in all sorts of discussions with meanings from time to time attributed by the magicians of the words of the moment. It happened for the term “How much”, introduced in physics, and for all its derivatives, perhaps also due to the misunderstandings caused by (erroneous) speeches also by famous scientists at the beginning of the intellectual exploration of this advanced field of our science, but certainly later due to of the evocative potential of “jumping”, “overcoming” and whatever else has gradually been attributed to the concept, above all in order to sell conceptions of the world and connected new age trinkets in every corner of the planet.

It happens today, in my sector, for the term “epigenetics” and for its various derivatives: apart from the different fields of application and the different scientific meanings that the researchers themselves attribute to the term, it is all a succession of the usual litanies of “overcoming”: of Darwinism, of reductionism, of determinism, of genetics, of traditional medicine and, in a word, of every discipline in which some salesman wants to accredit himself. Thus we take the easy path of putting true scientific knowledge in parentheses, using the word “epigenetics” to imply its overcoming and thus distance the public from those who know science, to attract them to themselves. Thus we find the following bold and captivating proclamations: “Epigenetics also puts an end to determinism, which holds genes responsible for everything. On the contrary, it encourages us to live our lives in a new state of freedom and makes us recognize that we ourselves are at the helm of the boat of our life. […] up to 30,000 different proteins can be created through our thinking and the influences of the environment. We are therefore not the victims of our genes (as conventional medicine would have us believe), but rather we can influence our health with the right information as well as joyful and positive thoughts and beliefs about life. This way you can even change the shape of a protein.”

Naturally, all in a website where the passage from epigenetic freedom and from the modification of the shape of proteins to the credit card is possible in an immediate way: by booking, for example, the “numerological theos”, or by donating to the site “alchemical vision” or buying books that would explain “how thought affects DNA and every cell”. Now, let’s make it clear once and for all: is it true that the environment can change the expression of an organism’s DNA? Of course it’s true, and there are many more mechanisms than those described today by epigenetics, such as methylation, histone modifications, the effects on the regulatory RNA network. Is it true that these changes are heritable, so that a parent’s life experience influences the phenotype of the offspring? Yes and no: in some organisms, such as plants and prokaryotes, this appears to be very widespread, but in vertebrates, and particularly in mammals, the bulk of the epigenetic modifications are reset in the gametes, so that the embryo receives a “blank slate” epigenetics for the vast majority of heritable traits. In addition, transmissible epigenetic traits are often reversible, ie they go back within a few generations; exceptions are the mechanisms through which real mutations are generated in the DNA, such as the deamination of methylated cytosines, but in this case the mutations are not necessarily adaptive, and fall within the usual path of generation of genetic variety and natural selection, as foreseen by the classical Darwinism.

Is it true that we can, with our thoughts, alter our DNA in a permanent and controlled way? No, at the moment not only do we not have evidence in this regard, but we don’t even have a hypothesis of a mechanism that we can put to the test; this is pure pseudoscience. Basically, apart from the obvious antics to sell products, the arguments of those who see epigenetics as a reversal of science as we know it are not convincing at all, for a number of reasons. Epigenetic inheritance, whether it is methylated DNA, histone modifications and the like, constitutes in very many, even if not all cases, a temporary “inheritance” which can cross one or two generations, but does not have the permanence to generate evolution of a population. In any case, the induced phenotype is controlled by nucleotide mutations in the DNA, whether reversible or not. There is nothing new here, certainly no new paradigm. And when you map adaptive evolutionary change and see where it resides in the genome, you invariably find that it’s based on changes in DNA sequence, DNA structure, or nucleotide changes in miRNAs or regulatory regions. There is not a single solid case where an adaptive change in a population has been caused by a change in an inherited trait that is not ultimately based on some induced change in the DNA. Epigenetics is part of modern science, and is fully within the agenda of molecular biology, evolution and genetics as we know them: a wonderful field of study and research, where there must be no space for more or less titled gurus who look at the portfolio of those who follow them.