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Greater than 98% Chimp/human DNA similarity?
Not any more. A common evolutionary argument gets reevaluated—by evolutionists themselves.
The >98.5% similarity has been misleading because it depends on what is being compared. There are a number of significant differences that are difficult to quantify. A review by Gagneux and Varki described a list of genetic differences between humans and the great apes. The differences include ‘cytogenetic differences, differences in the type and number of repetitive genomic DNA and transposable elements, abundance and distribution of endogenous retroviruses, the presence and extent of allelic polymorphisms, specific gene inactivation events, gene sequence differences, gene duplications, single nucleotide polymorphisms, gene expression differences, and messenger RNA splicing variations.
Specific examples of these differences include:
1. Humans have 23 pairs of chromosomes while chimpanzees have 24. Evolutionary scientists believe that one of the human chromosomes has been formed through the fusion of two small chromosomes in the chimp instead of an intrinsic difference resulting from a separate creation.
2. At the end of each chromosome is a string of repeating DNA sequences called a telomere. 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.
3. While 18 pairs of chromosomes are ‘virtually identical, chromosomes 4, 9 and 12 show evidence of being ‘remodeled. In other words, the genes and markers on these chromosomes are not in the same order in the human and chimpanzee. Instead of ‘being remodeled’ as the evolutionists suggest, these could, logically, also be intrinsic differences because of a separate creation.
4. The Y chromosome in particular is of a different size and has many markers that do not line up between the human and chimpanzee.
5. Scientists have prepared a human-chimpanzee comparative clone map of chromosome 21 in particular. They observed ‘large, non-random regions of difference between the two genomes. They found a number of regions that ‘might correspond to insertions that are specific to the human lineage.
These types of differences are not generally included in calculations of percent DNA similarity.
In one of the most extensive studies comparing human and chimp DNA,3 the researchers compared >19.8 million bases. While this sounds like a lot, it still represents slightly less than 1% of the genome. They calculated a mean identity of 98.77% or 1.23% differences. However, this, like other studies only considered substitutions and did not take insertions or deletions into account as the new study by Britten did. A nucleotide substitution is a mutation where one base (A, G, C, or T) is replaced with another. An insertion or deletion (indel) is found where there are nucleotides missing when two sequences are compared.
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ด้วยความปราถนาดีจาก "สยามทูเว็บดอทคอม" และเพื่อป้องกันการเปิดเว็บไซต์เพื่อหลอกลวงขายของ โปรดตรวจสอบร้านค้าให้แน่ใจก่อนตัดสินใจซื้อของทุกครั้งนะคะ อ่านเพิ่มเติม ...
