Is there enough time in the Bible to account for all the human genetic diversity?
Published: 17 September 2011 (GMT+10)
Jeff D. from the United States writes in response to the article Do you believe Richard Dawkins exists?:
Hmmm. Now that raises some questions for you. See, according to the creationists, all humans alive today are descended from 8 people who got off a Really Big Boat. Anyone who understands junior high genetics will know that 8 people have between them a maximum possible of 16 different alleles for each genetic locus (in reality, the 8 people on the Big Boat would have had even FEWER, since some of them were descended from others and thus shared alleles, but for the sake of argument we will give the creationists every possible benefit of the doubt and assume that they were ALL heterozygous and shared no alleles at all in common). That means, if the creationists are correct that “most mutations are deleterious” and that “no new genetic information can appear through mutation”, there cannot be any human genetic locus anywhere today with more than 16 alleles, since that is the MAXIMUM that could have gotten off the Big Boat.But wait …Today we find human genetic loci (such as hemoglobin or the HLA complex) that have well over *400* different alleles (indeed some have over *700* different alleles). Hmmmm. Since there could have only been 16 possible on the Big Boat, and since there are over 400 now, and since 400 is more than 16, that means that somehow the GENETIC INFORMATION INCREASED from the time they got off the Big Boat until now.That raises a few questions:
- if genetic mutations always produce a LOSS in information, like the creationists keep telling us, then how did we go from 16 alleles to over 400 alleles (perhaps in creationist mathematics, 400 is not larger than 16)?
- if these new alleles did not appear through mutations, then how DID they get here?
But wait—there’s more:Not only, according to creationists, must these new alleles have appeared after the Big Boat, but, according to their, uh, “theory”, all of these mutations must have appeared in the space of just *4,000 years*—the period of time since the Big Flood. That gives a rate of BENEFICIAL MUTATIONS, which add NEW GENETIC INFORMATION, of one every 10 years, or roughly two every generation—a much higher rate of beneficial mutation than has ever been recorded anywhere in nature. Nowhere today do we see such a rate anywhere near so high. So not only would I like to know what produced this extraordinarily high rate of non-deleterious mutations, but
what stopped it (indeed, what stopped it conveniently right before the very time when we first developed the technological means to study it)?But wait—we’re not done YET …Since less than 1% of observed mutations are beneficial (the vast majority of mutations are indeed deleterious or neutral and have no effect), that means for every beneficial mutation which added a new allele, there should have been roughly 99 others which did not. So to give us roughly 400 beneficial mutations would require somewhere around 40,000 total mutations, a rate of approximately 100 mutations in each locus EVERY YEAR, or 2,000 mutations per locus for EACH GENERATION. Do you know what we call people who experience mutation rates that high? We call them “cancer victims”.But wait, we’re STILL not finished …In order for any of those mutations to be passed on to the next generation to produce new alleles, they MUST occur in the germ cells—sperm or egg. And since any such high rate of mutation in a somatic cell (non-sperm or egg) would have quickly produced a fatal case of cancer, if the creationists are right this mutation rate could ONLY have occurred in the germ cells and could NOT have occurred in any of the somatic cells.
If one of our resident creationists can propose a mechanism for me which produces a hugely high rate of mutation in the germ cells while excluding it from any other cells, a Nobel Prize in medicine surely awaits—such information would be critically valuable to cancer researchers. But alas, no such mechanism exists. The rate of mutations made necessary by creationist “arguments” would certainly have killed all of Noah’s children before they even had time to have any kids of their own. In order to produce 400 beneficial alleles in just 4,000 years, humanity would have been beset with cancers at a rate that would have wiped them all out millenia ago.Explain, please
CMI’s Dr Robert Carter replies:
You are partially correct in your statements, but in other places you are way off the mark. Let me explain.
1) Yes, the Bible claims everyone living today is descended from only 8 people, but the amount of maximum diversity depends on which piece of DNA one is considering (nuclear, X, Y, or mitochondrial). We are well aware of the biblical predictions and I discussed them at length in my article Noah and Genetics.
2) Yes, most mutations are bad, but why would the current human population be limited to the number of alleles per locus that were on the Ark? Mutations since the Flood have added to the diversity. Please note, I take exception to the statement that creationists believe “no new genetic information can appear through mutation”. In fact, I have submitted an article to the Journal of Creation on the subject that will hopefully make it through peer review and appear there within the year (after revision, for our reviewers are very thorough) [Editor's note: This article has since appeared in print1]. I believe mutation can corrupt information, scramble information, and change it horizontally, but that it is utterly unable to account for the changes necessary for long-term evolution. Also, evidence is accumulating for the existence of genetic algorithms designed to facilitate changes to the DNA sequence. Dr. Peer Terborg has coined the term “variation inducing genetic elements” (VIGEs) and we happily incorporate them into the creation model. Since these changes would be caused by pre-programmed genetic modules, it is hard to call these changes “mutations”. The HLA genes in particular, as a vital part of the immune system, are pre-programmed to scramble, so using them as proof for your beliefs is an error on your part.
3) Your definition of “information” is wanting. ‘Variation due to high mutation load’ is not very satisfactory. Also, you chose the exceptions to the rule as proof for your point. In fact, the worldwide human population in particular has a surprisingly low diversity across almost the entire genome. This is the basis for the belief (among evolutionists) that humanity went through a near-extinction bottleneck event prior to the Out of Africa migration.
4) Given that some places in the genome do have high diversity, you still failed to account for the distribution of those variations worldwide. In fact, most variations come in two main flavors (Adam and Eve could have given us up to four) and these are generally found in all populations. When we find more variation than this, almost always the third, fourth, fifth, etc., versions are restricted to one subpopulation or another. These are mutations that have occurred since the Tower of Babel, and the exceptions (e.g., the ABO blood type locus,2 with three main alleles found across the world, one of which [O] is a broken version of another [A]) could have been due to mutations between Adam and Babel. Interestingly, deletion mutations, which are common within all people, are generally not shared among the various subpopulations. This is evidence of a young genome in rapid decay.
5) You are confusing “survivable” with “beneficial”. From evolutionary theory itself, we learn that most mutations are deleterious, but that most are also only slightly deleterious. In other words, they are only a little bit bad. Thus, finding variation within a certain gene is not evidence for beneficial mutation, but simply for mutation in general. One interesting thing about the evolutionary model is that slightly deleterious mutations are invisible to natural selection. Thus, bad mutations are inexorably accumulating over time in the human population and will eventually drive us to extinction (except that Jesus promised to return first). See Plant geneticist: ‘Darwinian evolution is impossible’ and From ape to man via genetic meltdown: a theory in crisis.
6) You are confusing (or confounding, depending on motive) “alleles” with “beneficial mutation”. I am quite surprised by this and am wondering if, in fact, you know what you are talking about. No geneticist believes that an allele has to be beneficial. Quite the contrary; most variation (with each variation called an “allele”) is caused by mutation and most mutations are bad. Therefore, most alleles represent genetic decay and the evolutionist assumes these will be weeded out by natural selection or through genetic drift. Evolution requires the accumulation of beneficial alleles over time, but there is precious little evidence that this occurs, as several notable evolutionists have admitted.3
7) Regarding the rate of mutation, certainly you are aware of the numbers being published by evolutionists? Consistently, we see rates of about 100 mutations per person, per generation, or more. Personally, I believe these rates are conservative, and I believe I can show this based on the methods used in the various papers that have supported these high numbers, but I can accept even this conservative estimate, for it flies in the face of the requirements of Darwinian evolution! These are not somatic mutations, which number in the trillions by the time a person reaches a mature age,4 but inheritable, germline mutations. This rate of mutation accumulation will drive us into extinction in much less than 1 million years. Without Jesus, we are doomed.
Conclusions: Despite your challenge, we do not need to explain your numbers for they represent several false assumptions, a misunderstanding of basic mutation theory, and confusion about simple definitions. The numbers are on our side, including the amount of current human diversity, the worldwide sharing of most of that diversity, the worldwide partitioning of high-variation alleles, measurable mutation rates, and the accumulation of deleterious alleles over time due to the ineffectiveness of natural selection to remove those alleles from the population.
I would encourage you to keep thinking about these things. In the end, you will be staring a lot of contrary data in the face and will have to come to a life-changing faith commitment about which side of the argument you will believe. From your letter, it is clear that you did not expect a reasoned response and did not think there were any data that contradicted your position. If you open your eyes, however, you will see that you were naïvely mistaken. The reality of human genetics stands in stark contradiction to the needs of evolutionary theory and belief in deep time. Pardon me for being blunt in some of what I said. Even though I felt your question was a bit over the top with its insults, both stated and implied, I tried to answer calmly and deliberately. In those places where I answered harshly, I was attacking the ideas behind what you said more than you as a person. At least, that was my intent.
- Carter, R. W., Can mutations create new information? Journal of Creation 25(2):92–98, 2011. Return to text.
- Criswell, D. ABO Blood and Human Origins. Acts & Facts 37(2):10, 2008; http://www.icr.org/article/abo-blood-human-origins/ Return to text.
- e.g. Lynch, M., Rate, molecular spectrum, and consequences of human mutation. Proceedings of the National Academy of Sciences (USA) 107(3):961-968, 2010. Return to text.
- About 1 somatic mutation per cell division! See the relevant section and footnotes in my article Neandertal Genome Like Ours. Return to text.