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  • Simpson Davenport posted an update 9 months, 1 week ago

    I’m nonetheless studying Shadow of Oz by Dr. Wayne Rossiter, and i definitely plan to submit a assessment of it when I am completed. Nonetheless, I needed to write a separate weblog submit about one point that he makes in Chapter 6, which is entitled “Biological Evolution.” He says:

    Up to now, the Nationwide Center for Biotechnology Data (NCBI), which homes all revealed DNA sequences (in addition to RNA and protein sequences), currently acknowledges nineteen totally different coding languages for DNA…

    He then references this web page from the NCBI webpage.

    This was a shock to me. As an impressionable young pupil on the College of Rochester, I was taught fairly definitively that there is only one code for DNA, and it is common*. This, after all, is commonly cited as proof for evolution. Consider, for instance, this assertion from The Biology Encyclopedia:

    For almost all organisms tested, together with humans, flies, yeast, and micro organism, the same codons are used to code for the same amino acids. Due to this fact, the genetic code is said to be universal. The universality of the genetic code strongly implies a common evolutionary origin to all organisms, even those wherein the small variations have advanced. These embrace a number of micro organism and protozoa which have a couple of variations, normally involving cease codons.

    Dr. Rossiter points out that this isn’t anywhere close to appropriate, and it presents severe problems for the concept that every one life descended from a single, frequent ancestor.

    To grasp the significance of Dr. Rossiter’s level, it’s worthwhile to understand how a cell makes proteins. The fundamental steps of the method are illustrated in the picture at the highest of this post. The “recipe” for every protein is saved in DNA, and it is coded by 4 different nucleotide bases (abbreviated A, T, G, and C). That “recipe” is copied to a special molecule, RNA, in a process called transcription. During that process, the nucleotide base “U” is used instead of “T,” so the copy has A, U, G, and C as its four nucleotide bases. The copy then goes to the place where the proteins are literally made, which known as the ribosome. The ribosome reads the recipe in units known as codons. Every codon, which consists of three nucleotide bases, specifies a selected amino acid. When the amino acids are strung collectively within the order given by the codons, the proper protein is made.

    The genetic code tells the cell which codon specifies which amino acid. Look, for instance, at the illustration at the top of the page. The first codon in the RNA “recipe” is AUG. Based on the supposedly common genetic code, these three nucleotide bases in that order are imagined to code for one particular amino acid:methionine (abbreviated as “Met” within the illustration). The subsequent codon (CCG) is presupposed to code for the amino acid proline (abbreviated as Professional). Every doable three-letter sequence (each possible codon) codes for a specific amino acid, and the gathering of all these possible codons and what they code for is usually called the genetic code.

    Now, as soon as again, according to The Biology Encyclopedia (and plenty of, many different sources), the genetic code is almost universal. Except for a number of minor exceptions, all organisms use the identical genetic code, and that factors strongly to the concept that each one organisms developed from a standard ancestor. However, in accordance with the NCBI, that isn’t even close to correct. There are all sorts of exceptions to this “universal” genetic code, and I might think that some of them result in critical problems for the hypothesis of evolution.

    Consider, for example, the vertebrate mitochondrial code and the invertebrate mitochondrial code. In case you didn’t know, many cells actually have two sources of DNA. The primary supply of DNA is within the cell’s nucleus, so it is known as nuclear DNA. However, Highlighting Guidelines Glow of cells that make up vertebrates (animals with backbones) and invertebrates (animals without backbones) also have DNA of their mitochondria, small structures that are answerable for making most of the vitality the cell makes use of to survive. The DNA present in mitochondria is called mitochondrial DNA.

    Now, based on the speculation of evolution, the sorts of cells that make up vertebrates and invertebrates (known as eukaryotic cells) weren’t the first to evolve. As an alternative, the sorts of cells present in bacteria (referred to as prokaryotic cells) supposedly developed first. Then, at a later time, one prokaryotic cell supposedly engulfed one other, however the engulfed cell managed to survive. Over generations, these two cells somehow managed to begin working collectively, and the engulfed cell turned the mitochondrion for the cell that engulfed it. That is the hypothesis of endosymbiosis, and despite its many, many issues, it’s the standard tale of how prokaryotic cells became eukaryotic cells.

    Nevertheless, if the mitochondria in invertebrates use a special genetic code from the mitochondria in vertebrates, and each of those codes are completely different from the “universal” genetic code, what does that inform us? It implies that the eukaryotic cells that ultimately evolved into invertebrates should have formed when a cell that used the “universal” code engulfed a cell that used a special code. Nonetheless, the eukaryotic cells that ultimately developed into vertebrates must have formed when a cell that used the “universal” code engulfed a cell that used yet one more completely different code. As a result, invertebrates will need to have evolved from one line of eukaryotic cells, whereas vertebrates should have advanced from a completely separate line of eukaryotic cells. But this isn’t doable, since evolution depends upon vertebrates evolving from invertebrates.


    Now, after all, this critical problem may be solved by assuming that while invertebrates advanced into vertebrates, their mitochondria also advanced to use a different genetic code. Nevertheless, I’m not really certain how that can be potential. In any case, the invertebrates spent tens of millions of years evolving, and through all those years, their mitochondrial DNA was arrange based on one code. How might the code change without destroying the perform of the mitochondria? At minimum, this adds one other job to the long, long record of unfinished duties needed to clarify how evolution might probably work. Along with explaining how nuclear DNA can evolve to produce the brand new buildings wanted to alter invertebrates into vertebrates, evolutionists should also clarify how, at the same time, mitochondria can evolve to make use of a special genetic code!

    Ultimately, it appears to me that this extensive variation in the genetic code deals a severe blow to the complete hypothesis of common ancestry, a minimum of the best way it’s at the moment constructed. Perhaps that’s why I hadn’t heard about "7 Highlighting Guidelines for the Perfect Glow till reading Dr. Rossiter’s excellent e-book.

    *Addition (4/3/2017): After talking with a biology professor for whom I have quite a lot of respect, I need to make an addendum. She says that these days, the term “universal genetic code” doesn’t necessarily imply that every organism uses the same set of codons for a similar amino acids. One might say that the genetic code is common in the sense that every one organisms use three nucleotide bases to define an amino acid, the codes can all be translated at the ribosome, and many others. I nonetheless think that these alternate genetic codes argue towards evolution, but it can be crucial to note that some evolutionists use the term “universal” with out implying that the codons are all the same among all organisms.