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Tuesday, April 3, 2012

Are mutations deleterious?

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 can not 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 ----- 
  1. 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)?
  2. 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 
  1. what produced this extraordinarily high rate of non-deleterious mutations, but
  2. 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

By: Lenny Flank

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