What I call the Great DNA Myth is a false teaching that continues to be spread by innumerable parties in the world of biology, even though there are very many other authorities in that same world who are telling us the teaching is false. The Great DNA Myth is the myth that inside DNA is some blueprint or recipe that specifies how to make a human body.
There are various ways in which this false idea is stated, all equally false:
- Someone may describe DNA or the genome as a blueprint for an organism.
- Someone may describe DNA or the genome as a recipe for making an organism.
- Someone may describe DNA or the genome as a program for building an organism.
- Someone may claim that DNA or genomes specify the anatomy of an organism.
- Someone may claim that genotypes (the DNA in organisms) specify phenotypes (the observable characteristics of an organism).
- Someone may claim that genotypes (the DNA in organisms) "map" phenotypes (the observable characteristics of an organism) or "map to" phenotypes.
- Someone may claim that DNA contains "all the instructions needed to make an organism."
- Someone may claim that there is a "genetic architecture" for an organism's body or some fraction of that body.
- Using a little equation, someone may claim that a "genotype plus the environment equals the phenotype," a formulation as false as the preceding statements, since we know of nothing in the environment that would cause phenotypes to arise from genotypes that do not specify such phenotypes.
Weaker formulations of this false idea include claims that DNA is "life's instruction book" or "the key to life" or "the book of life" or "the secret of life." While such rather vague assertions are not as explicitly false as the statements in the bullet list above, such formulations are equally misleading, as they insinuate the false claims in such a bullet list. Variations on these false statements above may use the term "genes" rather than DNA or genome. Such statements are equivalent to the statements above, because a gene is merely part of DNA (human DNA consists of roughly 20,000 genes).
There is no truth to the claim that DNA is a specification for anatomy. DNA merely specifies low-level chemical information such as which sequences of amino acids make up polypeptide chains that are the starting points of protein molecules. Many biology authorities (some of which I quote below) have confessed this reality that DNA does not specify anatomy. But the "useful stooge" that is the Great DNA Myth continues to be taught or suggested in the literature of biology by many other people. So now we have a very strange situation that might be described like this: biology's left hand is writing one thing, and biology's right hand is writing the opposite.
The US Government's Fictions About DNA
False claims about DNA are found not only in the literature of many biologists, but in some of the official proclamations of the US federal government. Examples can be found at the government site www.genome.gov. Below are some examples:
(1) At the government page here (https://www.genome.gov/about-genomics/about-genomics/educational-resources/infographics/Your-Genome-You) we are incorrectly told "The genome contains all the instructions for you to grow throughout your lifetime." This is not true. A genome (a person's DNA) merely specifies low-level chemical information, and does not specify how the progression from a tiny speck-sized zygote to a full adult body can occur. No instructions on how to build a human body are found in DNA, which does not even specify how to make any of the roughly 200 types of cells in the human body.
(2) The US government page here (https://www.genome.gov/about-genomics/fact-sheets/Deoxyribonucleic-Acid-Fact-Sheet) misleadingly states that "the complete DNA instruction book, or genome, for a human contains about 3 billion bases and about 20,000 genes on 23 pairs of chromosomes." In this sentence DNA is referred to as if it an instruction book for making a human. DNA is no such thing. All it contains is low-level chemical information, such as which amino acids make up particular proteins. The same page misleads us when it states this: "DNA contains the instructions needed for an organism to develop, survive and reproduce." DNA does have any instructions for how a full human body can develop from a speck-sized fertilized zygote, and DNA does not tell us anything about what we need to survive or reproduce.
(3) Another US government page (https://www.genome.gov/about-genomics/fact-sheets/A-Brief-Guide-to-Genomics) here falsely tells us that "Deoxyribonucleic acid (DNA) is the chemical compound that contains the instructions needed to develop and direct the activities of nearly all living organisms." DNA does not have instructions specifying the anatomical organization of a human, and does not "direct the activities of nearly all living organisms." DNA lists the structure of some chemicals you need; it does not direct your activities. The same page contains the untrue claim that "DNA contains the information needed to build the entire human body." DNA does not specify any anatomical structures in a human, and does not even specify how to make any of the 200 types of cells in they human body. The same page makes the extremely absurd claim that "virtually every human ailment has some basis in our genes." For example, when you get pneumonia or influenza or COVID-19 or many infectious diseases, you have got an ailment that does not have any basis in your genes. And when you are injured in an accident, that has no basis in your genes.
(4) On the page here (https://www.genome.gov/About-Genomics/Introduction-to-Genomics) we get the false claim that "Each genome contains the information needed to build and maintain that organism throughout its life." Genomes (DNA molecules) contain no instructions on how to build an organism or any of its cells. The rest of the page contains some equally misleading misinformation.
(5) The title of the NASA web page here (https://www.nasa.gov/feature/goddard/2022/life-blueprint-in-asteroids) refers to DNA as "the blueprint for life." The page makes the very untrue claim that DNA "contains the instructions to build and operate every living being on Earth."
(6) On the US government page here (https://www.genome.gov/outreach/unlocking-lifes-code-exhibition#) we are given a link to the video at https://www.youtube.com/watch?v=kEJ0eRaebIc (here). At the beginning of that video, we have a young boy say, "I have always found it really intriguing that everything about who we are and what we look like is controlled by these tiny molecules called DNA." This extremely false statement is not corrected, just as if the makers of the video wanted you to believe it is true.
A misleading visual on a US government web page
Some Experts Who Told Us the Truth About DNA
Below are some quotes by distinguished biology authorities revealing how false is the US government misinformation about DNA quoted above.
In this .pdf file, a professor of Mathematical Biology makes this statement:
"Although genes obviously play a role in development, knowing the genetic make-up of an organism does not allow us to understand the mechanisms of development—we may know that certain genes impart particular properties to certain cells, but how this then leads to tissue-level behaviour cannot be addressed by genetics."
That is basically a fancy way of saying that a fertilized egg does not become a baby by following a body plan stored in DNA.
On page 26 of the book The Developing Genome, Professor David S. Moore states, "The common belief that there are things inside of us that constitute a set of instructions for building bodies and minds -- things that are analogous to 'blueprints' or 'recipes' -- is undoubtedly false." The same expert (in a paper claiming massive misuse by others of the term "heritability") states, "Our DNA, we now know, does
not contain specific blueprint-like instructions about
traits."
Biologist Rupert Sheldrake says this about this issue:
"DNA only codes for the materials from which the body is constructed: the enzymes, the structural proteins, and so forth. There is no evidence that it also codes for the plan, the form, the morphology of the body. To see this more clearly, think of your arms and legs. The form of the arms and legs is different; it's obvious that they have a different shape from each other. Yet the chemicals in the arms and legs are identical. The muscles are the same, the nerve cells are the same, the skin cells are the same, and the DNA is the same in all the cells of the arms and legs. In fact, the DNA is the same in all the cells of the body. DNA alone cannot explain the difference in form; something else is necessary to explain form."
An evolutionary biologist notes that "the long-held belief that genes are the unique determinants of biological form in development and evolution has been challenged by an extensive number of commentators." Among these "extensive number of commentators" are the people mentioned above and the authors of this scientific paper, who note that "gene expression patterns cannot explain the development of the precise geometry of an organism and its parts in space."
Describing conclusions of biologist Brian Goodwin, the New York Times says, "While genes may help produce the proteins that make the skeleton or the glue, they do not determine the shape and form of an embryo or an organism." Massimo Pigliucci (mainstream author of numerous scientific papers on evolution) has stated that "old-fashioned metaphors like genetic blueprint and genetic programme are not only woefully inadequate but positively misleading." Neuroscientist Romain Brette states, "The genome does not encode much except for amino acids."
In a 2016 scientific paper, three scientists state the following:
"It is now clear that the genome does not directly program the organism; the computer program metaphor has misled us...The genome does not function as a master plan or computer program for controlling the organism; the genome is the organism's servant, not its master....Metaphorically, we can think of the genome as akin to a list of words, a vocabulary, which can be used to build and express a meaningful language; like a vocabulary, a genome by itself has no functional meaning. The genome is thus akin to a toolbox of DNA sequences that provide molecular tools as requested by the internal state of the organism and the state of the environment. One's genes cannot explain one's being: an organism is the expression of a dynamic and ongoing interaction between the state of its environment and its internal state, which includes its past history and its toolbox of DNA sequences."
In the book Mind in Life by Evan Thompson (published by the Belknap Press of Harvard University Press) we read the following on page 180: "The plain truth is that DNA is not a program for building organisms, as several authors have shown in detail (Keller 2000, Lewontin 1993, Moss 2003)." C.H. Waddington is described by wikipedia.org as "a British developmental biologist, paleontologist, geneticist, embryologistand philosopher who laid the foundations for systems biology, epigenetics, and evolutionary developmental biology." He stated, "The DNA is not a program or sequentially accessed control over the behavior of the cell." Scientist Jean Krivine presents here a very elaborate visual presentation with the title, "Epigenetics, Aging and Symmetry or why DNA is not a program." Scientists Walker and Davies state this in a scientific paper:
"DNA is not a blueprint for an organism; no information is actively processed by DNA alone. Rather, DNA is a passive repository for transcription of stored data into RNA, some (but by no means all) of which goes on to be translated into proteins."
Geneticist Adam Rutherford states that "DNA is not a blueprint," a statement also made by biochemistry professor Keith Fox. A press account of the thought of geneticist Sir Alec Jeffreys states, "DNA is not a blueprint, he says." B.N. Queenan (the Executive Director of Research at the NSF-Simons Center for Mathematical & Statistical Analysis of Biology at Harvard University) tells us this:
"DNA is not a blueprint. A blueprint faithfully maps out each part of an envisioned structure. Unlike a battleship or a building, our bodies and minds are not static structures constructed to specification."
"The genome is not a blueprint," says Kevin Mitchell, a geneticist and neuroscientist at Trinity College Dublin. "It doesn't encode some specific outcome." His statement was reiterated by another scientist. "DNA cannot be seen as the 'blueprint' for life," says Antony Jose, associate professor of cell biology and molecular genetics at the University of Maryland. He says, "It is at best an overlapping and potentially scrambled list of ingredients that is used differently by different cells at different times." Sergio Pistoi (a science writer with a PhD in molecular biology) tells us, "DNA is not a blueprint," and tells us, "We do not inherit specific instructions on how to build a cell or an organ." Michael Levin (director of a large biology research lab) states that "genomes are not a blueprint for anatomy," and after referring to a "deep puzzle" of how biological forms arise, he gives this example: "Scientists really don’t know what determines the intricate shape and structure of the flatworm’s head."
Agustin Fuentes, a professor of anthropology, states the following:
"Genes play an important role in our development and functioning, not as directors but as parts of a complex system. 'Blueprints' is a poor way to describe genes. It is misleading to talk about genes as doing things by themselves."
On the web site of the well-known biologist Denis Noble, we read that "the whole idea that genes contain the recipe or the program of life is absurd, according to Noble," and that we should understand DNA "not so much as a recipe or a program, but rather as a database that is used by the tissues and organs in order to make the proteins which they need."
In statements such as this, scientists "fess up" that the idea of DNA as a human specification is not true. Two other scientists "fess up" in a similar way when they write the following about genes in the journal Nature: "Population genetics is founded on a subset of coding sequences that can be related to phenotype in a statistical sense, but not based on causation or a viable causal mechanism."
Regarding the DNA as blueprint idea wikipedia.org article entitled “Common misunderstanding of genetics” lists the claim that “Genes are a blueprint of an organism's form and behavior” as one of the “common misunderstandings of genetics.” Jonathan Latham has a master's degree in Crop Genetics and a PhD in virology. In his essay “Genetics Is Giving Way to a New Science of Life,” a long essay well worth a read, Latham exposes many of the myths about DNA being a blueprint or master controller, and points out DNA does not even fully specify a protein. He states, "It is habitually, but lazily, presumed that DNA specifies all the information necessary for the formation of a protein, but that is not true."
Ian Stevenson M.D. cited quite a few biologists pointing out the genes and DNA cannot determine the form of an organism:
"Genes alone - which provide instructions for the production of amino acids and proteins -- cannot explain how the proteins produced by their instructions come to have the shape they develop and, ultimately, determine the form of the organisms where they are. Biologists who have drawn attention to this important gap in our knowledge of form have not been a grouping of mediocrities (Denton, 1986; Goldschmidt, 1952; B. C. Goodwin, 1985, 1988, 1989, 1994; Gottlieb, 1992; Grasse, 1973; E. S. Russell...Sheldrake, 1981; Tauber and Sarkar, 1992; Thompson, 1917/1942)."
Biologist B.C. Goodwin stated this in 1989: "Since genes make molecules, genetics...does not tell us how the molecules are organized into the dynamic, organized process that is the living organism." A paper by Stuart A. Newman (a professor of cell biology and anatomy) discussing at length the work of scientists trying to evoke "self-organization" as an explanation for morphogenesis states that "public lectures by principals of the field contain confidently asserted, but similarly oversimplified or misleading treatments," and says that "these analogies...give the false impression that there has been more progress in understanding embryonic development than there truly has been." Referring to scientists moving from one bunk explanation of morphogenesis to another bunk explanation for it, the paper concludes by stating, "It would be unfortunate if we find ourselves having emerged from a period of misconceived genetic program metaphors only to land in a brave new world captivated by equally misguided ones about self-organization."
Referring to claims there is a program for building organisms in DNA, biochemist F. M. Harold stated "reflection on the findings with morphologically aberrant mutants suggests that the metaphor of a genetic program is misleading." Referring to self-organization (a vague phrase sometimes used to try to explain morphogenesis), he says, "self-organization remains nearly as mysterious as it was a century ago, a subject in search of a paradigm."
Physician James Le Fanu states the following:
"The genome projects were predicated on the reasonable assumption that spelling out the full sequence of genes would reveal the distinctive genetic instructions that determine the diverse forms of life. Biologists were thus understandably disconcerted to discover that precisely the reverse is the case. Contrary to all expectations, there is a near equivalence of 20,000 genes across the vast spectrum of organismic complexity, from a millimetre-long worm to ourselves. It was no less disconcerting to learn that the human genome is virtually interchangeable with that of both the mouse and our primate cousins...There is in short nothing in the genomes of fly and man to explain why the fly has six legs, a pair of wings and a dot-sized brain and that we should have two arms, two legs and a mind capable of comprehending the history of our universe."
The false claim that DNA is a blueprint or recipe for making a human was denounced by Ken Richardson, formerly Senior Lecturer in Human Development at the Open University. In an article in the mainstream Nautilus science site, Richardson stated the following:
"Scientists now understand that the information in the DNA code can only serve as a template for a protein. It cannot possibly serve as instructions for the more complex task of putting the proteins together into a fully functioning being, no more than the characters on a typewriter can produce a story."
Writing in the leading journal Cell, biologists Marc Kirschner, John Gerhart and Tim Mitchison stated, "The genotype, however deeply we analyze it, cannot be predictive of the actual phenotype, but can only provide knowledge of the universe of possible phenotypes." That's equivalent to saying that DNA does not specify visible biological structures, but merely limits what structure an organism can have (just as a building parts list merely limits what structures can be made from the set of parts). A paper co-authored by a chemistry professor (Jesper Hoffmeyer) tells us this: "Ontogenetic 'information,' whether about the structure of the organism or about its behavior, does not exist as such in the genes or in the environment, but is constructed in a given developmental context, as critically emphasized, for example, by Lewontin (1982) and Oyama (1985)." A paper by Stuart A. Newman (a professor of cell biology and anatomy) refers to "misconceived genetic program metaphors."
At the Biology Stack Exchange expert answers site, someone posted a question asking which parts of a genome specify how to make a cell (he wanted to write a program that would sketch out a cell based on DNA inputs). An unidentified expert stated that it is "not correct" that DNA is a blueprint that describes an organism, and stated that "DNA is not a blueprint because DNA does not have instructions for how to build a cell." No one contradicted this person's claim, even though the site allows any of its experts to reply. "DNA is not a blueprint for an organism," states Templeton Prize-winning physicist and astrobiologist P. C. W. Davies. On page 26 of his book Biology as Ideology: The Doctrine of DNA, biologist Richard C. Lewontin stated this:
"We are not determined by our genes, although surely we are influenced by them...Even if I knew the complete molecular specification of every gene in an organism, I could not predict what that organism would be....Even if I knew the genes of a developing organism and the complete sequence of its environments, I could not specify that organism."
The same biologist on page 52 mentions only one of several reasons that can help explain why so many misstatements have been made about DNA, stating this: "Among molecular biologists who are professors in universities, a large proportion are also principal scientists or principal stockholders in biotechnology companies."
Why DNA as Body Blueprint Is a Childish Absurdity
If you ponder the simple fact that blueprints don't build things, you can start to get an idea of how nonsensical and childish is the claim that a human arises because a DNA blueprint is read. Blueprints have no power of construction. When buildings are built with the help of blueprints, it is because intelligent agents read the blueprints to get an idea of what type of construction work to do, and because intelligent agents then follow such instructions. But there is nothing in the human body below the neck with the power to understand and carry out instructions for building a body if they happened to exist in DNA.
Consider what goes on when you read a web page at a complicated site such as www.facebook.com or www.buzzfeed.com. What occurs is a very complicated interaction between two things: (1) a web page that is rather like a blueprint for how the page should look and act, and (2) an extremely complicated piece of software called a web browser, which is rather like a construction crew that reads the web's page blueprint (typically written in HTML), and then constructs very quickly a well-performing web page. If the web browser did not exist, you would never be able to get a well-performing web page. The construction of a three-dimensional human body would be a feat trillions of times more complicated than the mere display of a two-dimensional web page. Just as it is never enough to have just a web page without a web browser, having some DNA blueprint for building a body would never be enough to build a body. You would also need to have some "body blueprint reader/body construction system" that would be some system almost infinitely more complicated than a web browser, in order for a body to get built from a DNA blueprint if it existed.
We have no evidence that DNA contains any instructions for building cells or anatomy, and we also have no evidence for the existence of any such thing as a "body blueprint reader" in the human body, capable of reading, understanding and executing incredibly complicated instructions for building a human body. When you consider the amount of organization in a human body, you may start to realize the gigantic absurdity of thinking that a human specification can be found in some molecule merely listing low-level chemical information.
Instead of being written using some kind of coding system allowing unlimited expression, DNA is written in the coding system of what is called the genetic code, which is shown below. Such a system allows only the narrowest type of expression: the mere specification of amino acids, low-level chemical building blocks. We see below how this genetic code works. The letters A, T, C and G represent particular types of nucleotide base pair combinations in DNA.
The organization of large organisms is extremely hierarchical. Subatomic particles are organized into atoms, which are organized into amino acids, which are organized into protein molecules, which are organized into protein complexes, which are organized into organelles, which are organized into cells, which are organized into tissues, which are organized into organs, which are organized into organ systems, which are organized into organisms.
Cells are so complex they have been compared to cities. The diagrams you see of cells are enormously misleading, making them seem a thousand times simpler than they are. A cell diagram will show 20 or 30 organelles in a cell, but the actual number is typically more than 1000. A cell diagram will typically depict a cell as having only a few mitochondria, but cells typically have many thousands of mitochondria, as many as a million. A cell diagram will typically depict a cell as having only a few lysosomes, but cells typically have hundreds of lysosomes. A cell diagram will typically depict one or a few stacks of a Golgi appartus, each with only a few cisternae, but a cell will typically have between 10 and 20 stacks, each having as many as 60 cisternae. There are about 200 different cells in the human body.
Internally organisms are enormously dynamic, because of constant motion inside the body, the incredibly complex choreography of metabolism, and also because of a constant activity inside the body involving cellular changes. Just one example of this enormously dynamic acitvity is the fact that protein molecules in the brain are replaced at a rate of about 3% per day. A large organism is like some building that is constantly being rebuilt, with some fraction of it being torn down every day, and some other fraction of it being replaced every day. The analogy comparing a cell to a factory gives us some idea of the gigantically dynamic nature of organisms.
When we consider this enormously dynamic complexity, you may realize that the very idea of a blueprint for building a body is an absurdity, like imagining that the choreography of all of this year's ballets and Broadway shows could be expressed in a blueprint. To have a visual specification for building a human body, you would need something more like a multi-volume set of manuals containing a total of thousands of pages filled with color diagrams and tons of fine print. Even if such a specification existed in the human body, it wouldn't explain morphogenesis: because the specification would be so complex it would require some super-genius to understand it all and build things according to so complicated a specification.
The development of a human body from a one-cell speck-sized zygote can properly be described as a four-dimensional affair. It involves creating a three-dimensional physical structure, but also a structure that is so enormously dynamic that there is very much the time element involved everywhere. Time is often described as the fourth dimension. Specifying the physical progression of a human (with an enormous degree of internal dynamism) from a one-celled zygote requires four dimensions of information, something unavailable in the mere one-dimensional information that is the string-like sequence of DNA. As biologist Steven Rose has stated, "DNA is not a blueprint, and the four dimensions of life (three of space, one of time) cannot be read off from its one-dimensional strand."
Philosophy of Mind Implications of the Limits of DNA and Misstatements About DNA
What I have discussed here demonstrates some things extremely relevant to the philosophy of mind:
(1) Leading biology authorities may teach some childish falsehood, brazenly speaking as if the groundless idea was fact.
(2) This falsehood taught may be not merely some unproven idea, but an idea that is simply disproven and debunked by the known facts.
If this can happen in regard to DNA, it can happen in regard to brains. Just as many biology authorities routinely make claims about DNA contrary to known facts, many biology authorities make claims about brains contrary to known facts, such as the claim that memories are stored by synapse strengthening, an idea violently contrary to what we know about synapses and the
unstable dendritic spines they are attached to: their structural instability, the short lifetimes of their proteins (merely weeks or days), and the complete lack of any known thing in a synapse resembling an information storage system or an information storage code. Humans can remember things for 1000 times longer than the average lifetime of the proteins in synapses, and humans can form complex new memories instantly (much faster than the many minutes or hours needed to strengthen synapses).
The fact that DNA fails to explain morphogenesis is of the greatest importance to the philosophy of mind. The
failure of scientists to explain the physical origin of any human body suggests some great undiscovered causal reality helping to cause (in a top-down manner) the enormously impressive progression from a speck-sized zygote to the vast organization of the human body. If such a causal reality exists on the physical side, it then seems very reasonable to postulate such a causal reality existing on the mental side, helping to explain the origin of our minds and the preservation of our memories, not credibly explained by brain activity. For further explanation of this hypothesis of a top-down origin of the human mind, read my two posts
here.
Postscript: In the Guardian, science writer Phillip Ball
says this about the Human Genome Project that ended in 2003:
"But a blizzard of misleading rhetoric surrounded the project, contributing to the widespread and sometimes dangerous misunderstandings about genes that now bedevils the genomic age.So far, there have been few attempts to set the record straight. Even now, the National Human Genome Research Institute calls the HGP an effort to read 'nature’s complete genetic blueprint for building a human being' – the 'book of instructions' that 'determine our particular traits'. A genome, says the institute, 'contains all of the information needed to build and maintain that organism'. But this deterministic 'instruction book' image is precisely the fallacy that genomics has overturned, and the information in the genome is demonstrably incomplete. Yet no one associated with genomic research seems bothered about correcting these false claims...Plenty remain happy to propagate the misleading idea that we are 'gene machines' and our DNA is our 'blueprint'.
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