Human-chimp DNA similarities

Human-chimp DNA similarities
Claim: Human DNA is 99 percent similar to chimpanzee DNA, so, they have common ancestor.

What you need to know:

1- The claim itself is a logical fallacy (Jumping to conclusion) (Fallacy of Reification) as well as being inaccurate, read below.

2- Genetic information in all living creatures is encoded as a sequence of only 4 nucleotides (guanine, adenine, thymine, and cytosine) recorded using the letters G, A, T, and C. It is surely natural for the human body to bear some molecular similarities to other living beings, because they all are made up of the same molecules, they all use the same water and atmosphere, and they all consume foods consisting of the same molecules. Certainly, their metabolisms and therefore genetic make-ups would resemble one another. This, however, is not evidence that they evolved from a common ancestor. It is possible to explain this matter with an example; all construction in the world is done with similar materials (brick, iron, cement, etc.). They are constructed separately by using common materials. The same holds for living beings as well.

3- We know that DNA in cells contains much of the information necessary for the development of an organism. In other words, if two organisms look similar, we would expect there to be some similarity also in their DNA. The DNA of a cow and a whale, two mammals, should be more alike than the DNA of a cow and a bacterium. If it were not so, then the whole idea of DNA being the information carrier in living things would have to be questioned. Likewise, humans and apes have a lot of morphological similarities, so we would expect there would be similarities in their DNA. Of all the animals, chimps are most like humans,1 so we would expect that their DNA would be most like human DNA.

4- Similarity (‘homology’) is not evidence for common ancestry (evolution) as against a common creator. Why ?
Whether similarity is morphological (appearance), or biochemical, is of no consequence to the lack of logic in this argument.

5- Humans and chimps share about 96 percent of their sequence.1 so the difference is about 120,000,000 base pairs , The similarity isn't something unexpected. We already knew there was a vast amount of similarity between humans and primates both in terms of physical characteristics and structure. It is a mistake to assume that observing similarities necessarily brings you to the conclusion of common descent. Taxonomy based on physical characteristics was already a very well established science when the idea of common descent came on the scene.Would it mean that humans could have ‘evolved’ from a common ancestor with chimps? Not at all! The amount of information in the 3 billion base pairs in the DNA in every human cell has been estimated to be equivalent to that in 1,000 books of encyclopaedia size.2

6- About 35 million DNA base pairs differ between the shared portions of the two genomes, each of which, like most mammalian genomes, contains about 3 billion base pairs. In addition, there are another 5 million sites that differ along with a much smaller number of different chromosomal arrangements.1

7- As many as 3 million of the differences lie in crucial protein-coding genes or other functional areas of the genome.1

8- Moreover, the basic proteins are common vital molecules present in various other living things. The structure of the same kinds of proteins present not only in chimpanzee, but also in completely different living creatures, is very similar to that in humans.
For example:
  • Cats have 90% of homologous genes with humans, 82% with dogs, 80% with cows, 79% with chimpanzees, 69% with rats and 67% with mice. 3
  • Cows (Bos taurus) are 80% genetically similar to humans4
  • 99% of mouse genes turn out to have analogues in humans 5-75% of mouse genes have equivalents in humans6 , 90% of the mouse genome could be lined up with a region on the human genome 7
  • The fruit fly (Drosophila) shares about 60% of its DNA with humans 8
  • About 60% of chicken genes correspond to a similar human gene.9
9 - Telomeres in Chimpanzees and other apes have about 23 kilobases (a kilobase is 1,000 base pairs of DNA) of repeats. Humans are unique among primates with much shorter telomeres only 10 kilobases long.10

10 - The Y chromosome in particular is of a different size and has many markers that do not line up between the human and chimpanzee. Page's team found that the chimp Y chromosome has only two-thirds as many distinct genes or gene families as the human Y chromosome and only 47% as many protein-coding elements as humans. The remainder of the chimp and human genomes are thought to differ in gene number by less than 1%. More than 30% of the chimp Y chromosome lacks an alignable counterpart on the human Y chromosome, and vice versa, whereas this is true for less than 2% of the remainder of the genome.

11- If humans were entirely different from all other living things, or indeed if every living thing was entirely different, would this reveal the Creator to us? No! We would logically think that there must be many creators rather than one. The unity of the creation is testimony to the One True God who made it all.

- Biochemist Prof. Michael Denton made the following comments;

Each class at molecular level is unique, isolated and unlinked by intermediates. Thus, molecules, like fossils, have failed to provide the elusive intermediates so long sought by evolutionary biology… At a molecular level, no organism is "ancestral" or "primitive" or "advanced" compared with its relatives… There is little doubt that if this molecular evidence had been available a century ago… the idea of organic evolution might never have been accepted (Michael Denton, Evolution: A Theory in Crisis. London: Burnett Books, 1985, p. 290-291)
  1. New Genome Comparison Finds Chimps, Humans Very Similar at the DNA Level,2005, national human genome research institute
  2. Michael Denton, 1985. Evolution: Theory in Crisis
  3. Initial sequence and comparative analysis of the cat genome, 2007, http://genome.cshlp....17/11/1675.full
  4. The Genome Sequence of Taurine Cattle, 2009, http://www.sciencema...4/5926/522.full
  5. the mouse genome, Nature 420, 509 (5 December 2002)
  6. Lineage-Specific Biology Revealed by a Finished Genome Assembly of the Mouse, 2009
  7. The Mouse Genome And The Measure of Man December 2002 http://www.genome.go...pageID=10005831
  8. Background on Comparative Genomic Analysis December 2002,
  9. Researchers Compare Chicken, Human Genomes: Analysis Of First Avian Genome Uncovers Differences Between Birds And Mammals Dec. 10, 2004 http://www.scienceda...41208230523.htm
  10. (Kakuo, S., Asaoka, K. and Ide, T. 1999. ‘Human is a unique species among primates in terms of telomere length.’ Biochem Biophys Res Commun 263:308-314)
  11. The fickle Y chromosome - -

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