Chemistry Nobel Prize Based on Design Inference
This month's announcement of the Nobel Prize for Chemistry should cause design advocates to celebrate. We have just seen the biggest prize for science go to three biologists who made a design inference about genetic information. Tomas Lindahl, Paul Modrich, and Aziz Sancar shared the prestigious honor for their work on DNA repair mechanisms.
Of course, intelligent design was never mentioned in the Nobel Committee's announcement, either the popular version or the scientific version. We know also that the committee assumes that the repair mechanisms came about by a Darwinian process. In all likelihood, the winners are evolutionists, too. But think about it; their work was about information quality control -- a subject related to our new video that came out the very next day after the news. The Information Enigma asks three questions: (1) What is information? (2) How do we detect it? and (3) Where does it come from? The Nobel announcement suggests a fourth question: (4) How is information maintained?
The 1970s and 80s were a heady time for molecular biology, when the prizewinners were doing their research. The realization that life is based on digital information encoded in DNA was only a couple of decades old. DNA's structure had been revealed by Watson and Crick in 1953. Further work by Crick revealed the molecular basis of the genetic code in the "letters" of DNA bases (see Nature Scitable Education Library). Watson, Crick, and Wilkins won the Nobel Prize in 1962 "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material" (emphasis added.) Their work relied on findings by many other scientists, Nature Scitable reminds us, that were converging on the fundamental discovery that life is information-based.
This month's announcement is not the first time the design inference led to a Nobel Prize. The NIH Record, for instance, honors Marshall Warren Nirenberg as "discoverer of the genetic code" for his work on "the genetic code used by virtually all living organisms to translate the information in DNA molecules into protein structure." Nirenberg shared the Nobel Prize in 1968 with Robert W. Holley and H. Gobind Khorana.
The discovery of the genetic code and the discovery of the double helix structure of DNA in 1953 are generally considered the two transformational events in making biology a molecular science and are the fundamental basis of the subsequent sequencing of the billions of nucleotides in human DNA molecules, as part of the Human Genome Project, and the sequencing of the DNA of hundreds of other living organisms.
Sequencing would make no sense, obviously, if the order of the DNA bases were meaningless. Genome sequencing relies on the principle that the precise order of the bases is critical for function.
Another principle was becoming known around that time, too: information can be degraded. Erik Stokstad, writing in Science, describes how these two forces in conflict with each other -- information creation and degradation -- led Tomas Lindahl to think that something unnatural must be going on in the cell nucleus:
Biologists have long known that DNA wasn't rock solid. Blasts of xrays, for example, could cause mutations in cells. Yet most researchers believed that the molecule was inherently stable. After all, cancer and other genetic malfunctions are the exception, not the rule.Stokstad goes on to tell about the mechanism Lindahl found and published in 1974. Then he tells about the work of Modrich and Sancar, who independently "felt the light bulb go on" when thinking about this "hugely important topic" of information repair. Stokstad begins his article on that theme:
As a postdoc in the late 1960s, however, Lindahl began to have doubts. Samples of RNA in his experiments rapidly degraded when heated. Further experiments showed that even under normal conditions, DNA quickly suffered enough damage to make life impossible. A light bulb went on. "Lindahl had the critical insight," says biochemist Bruce Alberts of the University of California, San Francisco.
Lindahl began to search for enzymes that might repair this unseen damage.
Considering how much depends on the messages it bears, DNA is an alarmingly fragile molecule. It's vulnerable to UV light and mutagenic chemicals, as well as spontaneous decay. Life has survived through the ages because enzymes inside every cell ensure that DNA remains in proper working order. This year's Nobel Prize in chemistry, announced 7 October, recognizes three scientists who discovered key mechanisms for fixing the damage.We suggested that DNA repair is in some way "unnatural" -- why is that? Well, look what happens under natural conditions. The Nobel Committee tells us what would happen without "systems" to maintain the genetic information:
Each day our DNA is damaged by UV radiation, free radicals and other carcinogenic substances, but even without such external attacks, a DNA molecule is inherently unstable. Thousands of spontaneous changes to a cell's genome occur on a daily basis. Furthermore, defects can also arise when DNA is copied during cell division, a process that occurs several million times every day in the human body.What's "natural" is for DNA to degrade, and thus, the information that rides on it. Mutations lead to cancer and other life-threatening diseases. We humans know all about the necessity of tools to fix things. So do cells; the cell keeps a "toolbox for DNA repair," the Nobel headline quips. The New York Times uses similar concepts, in its own words, to describe how the cell "fights" the natural tendency toward chemical chaos:
The reason our genetic material does not disintegrate into complete chemical chaos is that a host of molecular systems continuously monitor and repair DNA. The Nobel Prize in Chemistry 2015 awards three pioneering scientists who have mapped how several of these repair systems function at a detailed molecular level.
The human body is made up of trillions of living cells, each containing a coiled mass of DNA that if straightened out would extend about six feet. In turn, each strand carries the thousands of genetic instructions needed to run the body.Notice that what they found was not simply mechanisms that "repair DNA" as if any order of base pairs would do. No; they found systems and mechanisms that worked to maintain the genetic instructions needed to run the body (i.e., functional information).
But the DNA molecule is unstable. The genome of each cell undergoes thousands of spontaneous changes each day. And DNA copying for cell division and multiplication, which happens in the body millions of times daily, also introduces defects. Finally, DNA is damaged by ultraviolet light from the sun as well as by industrial pollutants and natural toxins -- those in cigarette smoke, for example. What fights pandemonium are DNA repair mechanisms.
So it's fair to say that what is "natural" is the spontaneous degradation of information. Mechanisms designed by a mind, by contrast, can overcome the natural tendency toward "pandemonium." We know from experience that it takes the guidance of goal-directed intelligence to proofread and correct errors in digital code. The BBC News aptly calls this process debugging. Ever see an unguided debugger of computer code?
To address those defects, a host of molecular systems continuously monitor and de-bug our genetic information. The three new laureates mapped in detail how some of these mechanisms worked.
It's not necessary to use the phrase "intelligent design" to recognize it in action. Nor is it necessary to know the personal beliefs of the Nobel laureates. They made a design inference; that's what counts. Quality control, information monitoring, error correction systems -- these are phrases rich with design concepts.
We're glad that three intelligent scientists, Lindahl, Modrich and Sancar, received the world's highest scientific honors for uncovering "a molecular system that constantly counteracts DNA collapse" by what can fairly be called intelligent design. Whether or not anyone in fact calls it ID, the 2015 Nobel Prize for Chemistry reflects the validity and fruitfulness of the design inference for top-flight scientific research.