In a previous post entitled "Misleading Statements in a Recent Nobel Prize Announcement" I analyzed quite a few misleading statements in the press release (and a supplementary document of that release) issued by a Nobel Prize committee announcing the year 2024 Nobel Prize in Chemistry. The press release I discussed was not the only misleading press release issued in 2024 by a Nobel Prize committee. There were also bad errors in the press release announcing the Nobel Prize in Physiology or Medicine.
In its second sentence that press release contained this piece of fiction: "The information stored within our chromosomes can be likened to an instruction manual for all cells in our body." The information referred to is DNA, also called the genome. DNA consists mainly of genes. But neither DNA nor its genes contain any such thing as an instruction manual for cells. DNA has no specification of how to build a cell or any of its organelles, or how to maintain or correctly position any cells. DNA does not even specify how to construct the protein complexes that make up organelles.
The level of organization in the body is as follows: a body consists mainly of organ systems and a skeletal system; organ systems are built mainly from organs; organs are built from tissues; tissues are built from cells; cells are built from many types of organelles; organelles are built mainly from proteins complexes; protein complexes are built from proteins; and proteins are built from amino acids. The chromosome and its DNA does not have any specification of how to construct any of these levels higher than protein molecules. So it is a huge falsehood to claim that "the information stored within our chromosomes can be likened to an instruction manual for all cells in our body." DNA does not tell how to make a cell or any of the main components of a cell; and DNA does not tell cells how to act or where they should go in the body.
The Nobel Prize press release contained the following paragraph. I will put the false statements in boldface underline:
"The information stored within our chromosomes can be likened to an instruction manual for all cells in our body. Every cell contains the same chromosomes, so every cell contains exactly the same set of genes and exactly the same set of instructions. Yet, different cell types, such as muscle and nerve cells, have very distinct characteristics. How do these differences arise? The answer lies in gene regulation, which allows each cell to select only the relevant instructions. This ensures that only the correct set of genes is active in each cell type."
No, gene regulation does not constitute even a half-explanation of why we end up with different cell types. Gene regulation refers to a cell's use or non-use of certain types of proteins. But that does not even half-explain why the human body has 200 different types of cells, with so many different functions, structures and characteristics. Similarly, if there were some person traveling to different construction sites, and merely saying things such as "use copper pipes" and "don't use cinder blocks" and "use steel beams" and "don't use wood 2 by 4's," that would never explain how one construction site might produce a stone church and another construction site might produce a mansion and another construction site might produce a shopping mall. Nowhere in chromosomes or DNA are there any instructions for building a cell or any of its organelle components, and neither chromosomes nor DNA nor its genes has any instructions on how to maintain, position or reproduce a cell.
The press release in question announced the awarding of a Nobel Prize for the discovery of a microRNA by Victor Ambros and Gary Ruvkun. A microRNA is a very tiny chemical unit that is only 18 to 25 nucleotides. About 1000 microRNA molecules have been discovered. Molecules so small with so little information are utterly incapable of explaining the vast mystery of why there arises so many different types of enormously complex cells specialized for different biological purposes.
The Nobel Prize press release I am discussing gives us the extremely misleading visual below:
The diagram above misleads us badly in three different ways. First, it omits two different layers of organization, and gives us the profoundly misleading idea that cells are directly made from proteins. The truth is that cells are made from extremely complex components called organelles, which are built from extremely complex protein complexes, which are built from protein molecules. Second, the diagram misleads us badly by giving us a visual suggesting that cells are very simple. We see a cell that has only a few organelles. The truth is that human cells typically contain very many thousands of organelles. Third, the diagram makes proteins look like very simple things with only a few parts. Human proteins have an average of about 450 amino acids each, which must be very specially arranged for them to perform their functions.
Schematic diagrams of cells are constantly misleading us by depicting cells with only a few organelles. Specifically:
A cell diagram will typically depict a cell as having only one or a few mitochondria, but human cells typically have many thousands of mitochondria, as many as a million.
A cell diagram will typically depict a cell as having only only one or a few lysosomes, but human cells typically have hundreds of lysosomes.
- A cell diagram will typically depict a cell as having only a few ribosomes, but a human cell may have up to 10 million ribosomes.
A cell diagram will typically depict one or a few stacks of a Golgi apparatus, each with only a few cisternae. But a cell will typically have between 10 and 20 stacks, each having as many as 60 cisternae.
A cell diagram will rarely even depict a microtubule, although according to the paper here "cells can contain from just a few to many hundreds of microtubules (Aikawa, 1971; Osborn & Weber, 1976)." The membranes of cells are extremely complicated structures, consisting of four layers, with each layer being populated by many types of proteins each consisting of hundreds of well-arranged parts. Some of this complexity could easily be shown by a "closeup circle" in a cell diagram, showing a closeup of part of the membrane. But we rarely see any such depiction of the complexity of the cell membrane, and cell diagrams almost always have cell membranes depicted as featureless things looking as simple as the surface of a balloon.
The cytosol of a cell is typically depicted as if it were a simple fluid like water. But the cytosol is actually loaded with many types of complex protein molecules needed for cell function.
There is no excuse for the continuation of misleading cell diagrams in the literature of biology. For the past twenty years it has been easy to use computer graphics to make very sophisticated high-resolution diagrams capable of properly representing the complexity of cells. But almost no one is creating such diagrams, and we continue to see most cell diagrams looking like something hand-painted in the 1950's.
The type of cell diagrams we usually see in biology literature are misrepresentations as absurd as trying to depict gigantic skyscrapers like the Empire State Building or the 828-meter-tall Burj Khalifa tower by using ridiculously simplistic diagrams like this:
We get more very misleading talk later in the Nobel Prize press release with this statement:
"Gene regulation by microRNA, first revealed by Ambros and Ruvkun, has been at work for hundreds of millions of years. This mechanism has enabled the evolution of increasingly complex organisms."
The word "enable" means "give (someone or something) the authority or means to do something." The biological and chemical requirements for complex organisms are endless and ubiquitous, and most involve things vastly more complex than microRNA molecules, which are very small molecules. So to claim that mere microRNAs "enabled the evolution of increasingly complex organisms" is to misspeak badly. A correct statement would be that microRNAs are some of the least complex of the enormously high number of things needed for the appearance of organisms as complex as humans.
The diagram below correctly describes the levels of organization in the human body, and tells us what is not specified by DNA.
We have in this Nobel Prize press release and its diagram a repetition of one of the most misleading claims of biologists between 1975 and 2024: the groundless claim that genes contain programs for development. DNA is not a program, and the genes that make up DNA are not any program that forms organisms. DNA does not have any of the control structures (such as if/then statements) found in computer programs. DNA does not specify the growth of an organism, and does not know or state anything about organisms or their cells.
Professor 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." 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)." Developmental biologist C/H. Waddington stated, "The DNA is not a program or sequentially accessed control over the behavior of the cell." 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." A paper by cell biologist Stuart A. Newman states, "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."
Part of the press release helps reveal the utter inadequacy of anything discovered by the awarded scientists to explain the mountain-sized mystery of cell differentiation. We read this: "Ambros and Ruvkun performed further experiments showing that the lin-4 microRNA turns off lin-14 by binding to the complementary sequences in its mRNA, blocking the production of lin-14 protein." These guys merely found
an off-switch for a particular protein. That cannot be more than just the tiniest piece in a gigantic puzzle with thousands of missing pieces, since cells use 20,000+ proteins, and since off-switches can't explain 200 very diverse types of enormous organization as we see in cells. And since tiny little microRNAs don't even have as much information as found on a single sentence of this post, it's pretty laughable to be elevating them to be things explaining the variety of human cells, things far more complex than any blog post I've ever written.
The false claim made by the Nobel Prize press release (that gene regulation or gene expression explains why we have 200 different types of cells with vastly different sizes, structures, locations and functions) has been stated by many sources. False information about genes and DNA is super-abundant in the literature of biology, where groundless fictions about DNA have been steadily told for 75 years. The main reason such misinformation has been passed around in my post here. The same post quotes dozens of scientists and doctors who told us the truth about such matters, telling us that DNA is no blueprint, recipe or program for building a body or any of its cells.
A phrase such as "gene expression" or "gene regulation" is vacuous as an explanation for why cells have different structures and different locations and why they use different proteins. Gene expression refers to what proteins a cell uses and how often they are used. Rather than being an explanation for why different cells are different, the phrase "gene expression" is one aspect of how they are different. Appealing to "gene expression" as an explanation for why two cells are different is as vacuous as answering a question of "how come a computer is arranged differently from a refrigerator" by saying "because they have different parts in different places." Similarly the term "gene regulation" refers to a large variety of different complicated factors that differ when different cells end up with different concentrations of proteins. But as an explanation for why two cells are different, the phrase "gene regulation" is as vacuous as trying to answer the question of "how come a computer is arranged differently from a refrigerator" by using a phrase such as "part placement differences." Having within it no concept or specification of a cell, DNA has no "gene regulator" controlling how many proteins of different types go into particular cells. Instead of referring to one discrete thing, the term "gene regulation" refers to dozens of scattered little things that differ when different types of cells arise. Appealing to "gene regulation" as an explanation is as vacuous as trying to explain why a cathedral looks different from a factory by appealing to "assembly differences" or "construction methodology." When used as an attempted explanation, the obscure phrase "gene regulation" is an example of hand-waving. Different gene regulation in different cells is one aspect of different cells being different, not an explanation of why they are different.
As shown by this post and a previous post of mine, the year 2024 has proven that we should have no great confidence in the claims made by press releases announcing Nobel Prize awards. Nobel Prize press releases should be treated with the same suspicion and critical scrutiny we should have for university press releases announcing science research. Such press releases are very often guilty of very bad groundless boasting and misleading claims.
Earlier in this century a biologist spoke truthfully about how little biologists understand cells, stating this:
"Cell biology is a mystery for many reasons one
of which is the lack of basic knowledge. This may
be the fault of scientists or simply a failure in basic
information at the level of common contemporary
knowledge. The well known sentence of Socrates:
'I know that I know nothing' is as true in cell
biology as in other scientific fields. This sentence
was modified by Lloyd in 1986 who claimed: 'The
closer we look, the less we see'. I would like to
modify this sentence yet again as a cell biologist and
microscopist: 'The closer we look, the less we know
about.' ... Everyone involved in cell
biology, is surprised how limited is our knowledge
about the various cell compartments....It should now be mentioned
that our knowledge even of basic cell organelles,
including their various functions, is very limited....We
know something about cell organelles, including
various nuclear compartments, but most of their
functions are waiting for further and better
clarification....Depending on
conditions, selected genes may be repressed or
derepressed and activated giving to rise to the
particular cell lineage with characteristic cell
structures and functions. On the other hand, such
transformations, including the homing of the
transformed cells are also very mysterious although
both these processes are empirically used in clinical
medicine."
A year 2022 statement by Intel claims that some analysis technique is "beginning to unravel the mystery of cell differentiation." In general when scientists say that they are merely "beginning to unravel" some great mystery, it is a confession that the mystery is still very much not understood by them. Humans don't understand how different cell types arise in the human body, contrary to the boast of the Nobel Prize committee that this is explained by "gene regulation."
In the Nobel Prize press release I have criticized, there is a link to some speech given describing the 2024 award for the Nobel Prize in Medicine and Physiology. The speech gives us a very clumsy analogy in which the construction of a cell is compared to the performance of some symphony, and individual genes are compared to instrument players. The analogy is inappropriate because musicians work with a musical score exactly specifying how a symphony should sound, but DNA and its genes are nothing like a specification of any cell or any organ or any adult body. We read this:
"MicroRNAs are conductors with a special ability. Instead of passionately making gestures to either amplify or dampen music intensity, microRNAs tell musicians only when to quiet down or take a break. ‘You there, play softer! You, take a break!’ "
It's obvious from this analogy that individual MicroRNAs are mere "bit players" or minor cogs in the gigantically complicated process by which enormously organized cells are originated and vastly organized organism bodies are constructed. The awarded discovery merely involves finding one piece in a gigantic jigsaw puzzle which has almost all of its pieces still undiscovered, as illustrated in the visual below.
In many of these cases that are hailed as progress in understanding things, there may be no real progress at all, but just some explanatory "robbing Peter to pay Paul." For example, let us suppose that there is some gene which has its rate of expression slowed down at some particular point in some type of cell. Let us suppose that someone postulates that this occurred because some microRNA sent a message at some point telling the gene to slow down. That's just a mere speck of explanatory progress. We've simply gone from "how did the gene know to slow down at this particular time in this particular cell?" to the equally great mystery of "how did the microRNA know that it should signal the gene to slow down at this particular time in this particular cell?" The problem is that DNA has no actual specification of cells or the organelles that make up cells. So from a mechanistic or reductionist standpoint, none of these chemicals should know anything about what it should be doing at a particular time to help achieve some grand result such as the construction of a particular type of vastly organized cell, or its placement in the correct position in a human body.
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