Mutations, epigenetics and the question of information
Published: 29 October 2011 (GMT+10)
Creationist arguments in biology are often represented by slogans such as “mutations cannot increase information” by both creationists and evolutionists. However, these slogans oversimplify and tend to misrepresent creationist arguments regarding genetics and molecular biology. Creation biologists Dr Don Batten and Dr Jean Lightner address some of these simplifications.
Richard M. from the United States writes in response to Hebrew Scriptures as an aid to developing a creationist taxonomy. Creation biologist Dr Jean Lightner replies with comments interspersed:
This is the clearest statement that I have seen by a creationist which acknowledges that mutation increases genomic information. Alleles beyond those filtered by the bottleneck mentioned above cannot be dismissed as “being already present in the population” or as arising from “lateral exchange of genetic material.” Logic demands that they must have arisen de novo. The phenotypic traits that they specify could not have been present in the (immediate post-bottleneck) founder population.
By definition, a mutation in a gene results in a new allele. There is no question that mutation (defined as any change in the DNA sequence) can increase variety in a population. However, it is not obvious that this necessarily means there is an increase in genomic information.
If one attempts to apply Shannon’s theory of information, then this can be viewed as an increase. However, Shannon’s theory was not developed to address biological information. It is entirely unsuitable for this since an increase of information by Shannon’s definition can easily be lethal (and an increase in randomness increases Shannon ‘information’).
I realize that the ‘no new information’ argument is popular among creationists at the lay level. Many biologists, including myself, don’t use it for several reasons. First, it is very difficult to define genomic information. This is partially because there are so many levels of information in the genome and also because there is so much we still don’t know.
Secondly, the creation model includes a Creator. Since man has programming abilities, so does his Creator, and limited information (depending on how one defines it) may be able to arise as a result of genomic programming. In other words, God designed the genome at Creation to allow for his creatures to adapt and fill the earth (Genesis 1:22; 9:1) since He intended the earth to be inhabited (Isaiah 45:18). This is why today we can find some hares in the Arctic (Lepus arcticus) and others in the desert (Lepus capensis). Evolutionists require new information to arise by naturalistic processes rather than intelligently designed processes. That was one point in my MC1R article [Ref. 1 in the article being commented on]. It does not appear that all of the new alleles arose by naturalistic processes (random mutation plus natural selection), suggesting that the neo-Darwinian model is inconsistent with reality on this point.
Have the mutations documented in MC1R added biological information in the sense necessary for molecules-to-man evolution? The majority of mutations fall into two basic classes: loss of function and constitutive activity. In both cases the receptor is removed from the complex biological pathway it was part of; that is, it no longer responds to its signaling molecules. Instead, it is either always shut off (loss-of-function) or always turned on (constitutively active). While this may at times be useful, and may even be a programmed change, it does not support the conjecture that complex biochemical pathways have arisen via evolution.
I thank Dr. Lightner for her recognition that whatever “models” creationists bring forth to account for the natural world must be subject to the constraints that natural science has discovered.
Thank you for the compliment, though I know of many creationary researchers who work diligently to keep our models consistent with reality. I enjoy being a creationary researcher because the wealth of information in the current scientific literature in my field is far more easily understood in a creationary worldview than an evolutionary one.
Errol B. from Australia writes:
Thank you for your ministry. As a subscriber to ‘Creation Magazine’ I have acquired much knowledge from your publications, DVD’s and website. To start with, there was enough to give me confidence that there are answers to atheistic questions but for me, the lights really went on while watching Creation Live, episode 4 (Changes In Living Things Part 2, Mutations) on your web site with Richard Fangrad explaining H. Pylori bacterial resistance to antibiotics. I suddenly realized the types of mechanisms operating in living things that cause beneficial changes to living things in a given environment like the Rapid Tomcod evolution by pollution in New York’s Hudson River Creation Vol. 33, No. 4, 2011, p. 22 and why it’s the opposite of evolution. It’s obvious the average atheist & unfortunately most fellow Christians don’t get it, however as I’m learning more, some answers need clarifying (to me at least). Dr Carl Werner’s highly recommended book Evolution: The Grand Experiment Volume 1, The Quest for an Answer Chapter 3 explains how past scientists got it wrong with theories of ‘Acquired Characteristics’ example: If a man becomes a body builder, Darwin thought that enlarged muscles from exercise would be passed on to the next generation. The same goes with horses becoming giraffe-like by stretching their necks to reach a food source or sun tanned skin causing the next generation to have darker skin with the reasoning that various affected cells somehow send messages to the reproductive cells over generations and over vast amounts of time enabling one kind of animal to turn into another. On the other hand, I recently watched a DVD called DNA by Design with Stephen C. Meyer. Dr Meyer explains how the cells have seriously sophisticated genetic programs just like computer programs, only more complex. These genetic programs have folders within super folders within super-dooper folders and ‘if/then’ sub-routines triggered by environmental factors that can switch genes on & off. Clearly no new information is being added to the genome therefore any beneficial change would be limited to already existing genetic information.
Are the acquired characteristics Dr Werner refers to, different to the adaptations Dr Meyer refers to? I suspect Dr Werner is referring only to imaginary changes outside existing genes that were supposed to build completely new parts while Dr Meyer presents an extraordinary case for intelligent design allowing living things to change and adapt within limits but always use existing genetic information restricting it to remain within its kind. Do you know of any examples to what Dr Meyer refers that could be mistaken for the acquired characteristics of which Dr Werner refers? When I watched DNA by Design, I immediately thought of Dr Werner’s referring to the discredited theory of acquired characteristics. If I were an atheist I would try to discredit Dr Meyer or reinstate the theory of acquired characteristics discrediting Dr Werner. Even if atheists have tried this, would it be evidence that supports evolution? I think not. Can you confirm or clarify these two concepts? Can you explain in layman’s terms the mechanism or an example of how environmental factors can trigger gene expression to allow a living thing to change and adapt?
CMI’s Dr Don Batten responds:
Thanks for your encouragement regarding what we do. Thanks for sharing some of your journey with us; it is particularly encouraging when our friends ‘get it’.
Regarding your question, Dr Meyer is, I believe, referring to epigenetic changes. These are quite different to acquired characteristics that are permanently inherited (the Lamarckian concept).
Epigenetic changes are indeed a response to the environment, but they entail switching existing genes off (or on again), not creation of new genes.
This is from Dr Rob Carter’s recent paper on this topic (Darwin’s Lamarckism vindicated?):
“Epigenetics deals with non-permanent modification of the genome. Like turning on and off a light, genes can be turned on and off as well. The main engine for this is called DNA methylation, where a methyl group (–CH3 ) is attached to specific cytosine residues. The bulky methyl group attached to the DNA blocks the transcription machinery, so a methylated gene is effectively silenced. Methylation is strongly associated with the environment. Thus, the environment can affect the way an organism behaves. More importantly, evidence is slowly accumulating that methylated genes can be transmitted from one generation to the next. Even more importantly, methylation can be reversed. This field has given us terms like ‘epialleles’ (‘epi’ means ‘upon’) and ‘paramutation’ (‘para’ means ‘alongside’) to describe non-permanent variation and non-permanent changes, respectively, that occur in the genomes of various organisms. Examples of epigenetic inheritance range from petal number in plants to coat color in mice. In the mouse example, in certain instances the coat color of young mice is affected by the diet of the mother. The coat color is also able to pass to the grand-mice, but the effect wears off over the generations if the diet is changed. The removal of the environmental trigger allows the methylation patterns to change back to the original state.”
Note that these are non-permanent changes and can be reversed. However, they make it even more difficult for natural selection to work as evolutionists would like.
Epigenetic changes can be inherited (e.g. a mouse mother’s diet can affect the coat colour of the offspring). However, if the diet of the offspring follows a different path, then the epigenetic characters that cause the different coat colour can be reversed in subsequent offspring.
So these changes are not permanent and do not contradict the basic principles of inheritance that Dr Werner outlined.