12 % of the DNA Differs Amongst Human Races and Populations
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The Human Genome Project found all humans to have a 99.9 % similar genetic content and identity, but this is challenged by a new more detailed research suggesting a higher genetic diversity, with further medical and evolutionary implications.
Previous studies focused on analyzing polymorphism (variation) in DNA nucleotidic bases. But the new approach tackled deletions or duplications of code among relatively long sequences of individual DNA and then compared the so-called copy number variations (CNVs) across individuals from different human breeds. This method uncovered a complex, higher-order variation in the code and better explains why some populations or races are vulnerable to certain diseases and respond well to specific drugs, while counterparts swiftly fall sick or never respond to treatment.
technical breakthroughs, a faster, accurate sequencing of DNA and a powerful software programme to spot the CNVs allowed the new approach. 1,447 CNVs were located in roughly 2,900 genes, which means around 12 % of the human DNA. "Each one of us has a unique pattern of gains and losses of complete sections of DNA," said Matthew Hurles from Britain's Wellcome Trust Sanger Institute. "One of the real surprises of these results was just how much of our DNA varies in copy number. We estimate this to be at least 12 % of the genome."
"The copy number variation that researchers had seen before was simply the tip of the iceberg, while the bulk lay submerged, undetected. We now appreciate the immense contribution of this phenomenon to genetic differences between individuals."
Some missing or duplicated DNA fragments are very large, thus CNVs might have a big impact on gene expression. About 16 % of genes related to disease have been found to possess CNVs, like those involved in the rare DiGeorge, Williams-Beuren and Prader-Willi syndromes or more common schizophrenia, cataracts, spinal muscular atrophy and atherosclerosis. But kidney disease, Parkinson's, Alzheimer's and vulnerability to malaria and the human immunodeficiency virus (HIV), which recent research has blamed on single-letter variations in the gene code, are also suspected for CNVs. "The stage is set for global studies to explore anew... the clinical significance of human variation," said Huntington Willard at Duke University in North Carolina.
The new data also shows that our species is so recent that the vast majority of CNVs, around 89 %, was found to be shared among the 269 people belonging to Mongoloid Race (Japanese and Chinese), African Negroid (Yoruba Nigerians) and Caucasoid (of Northern and Western European ancestry). But there are also widespread specific differences in CNVs according to the race and even inside the same race according to population (geographical origin). This means that over 200,000 years or so, natural selection favored subtle variants allowing different humans populations to adapt to their different environments, with specific climate, pathogens, and food resources.
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|Comment #1 by: gab1 on 24 Nov 2006, 09:28 UTC|| reply to this comment|
"But kidney disease, Parkinson's, Alzheimer's and vulnerability to malaria and the human immunodeficiency virus (HIV), which recent research has blamed on single-letter variations in the gene code, are also suspected for CNVs."
ok... so out of 3,200,000,000 letters in the DNA code you just misplace/mutate ONE SINGLE-LETTER out of its right place and you get something as bad as HIV&all the other serious diseases???
seems that 99.(9)% of the mutations damages°enerates the DNA code, they're decreasing the amount of useful/correct genetic information throughout the process of natural selection/adaptation... so the facts are that all the living things are INVOLVING and NOT evolving...
a specie highly adapted to a specific enviroment has lost genetic information and can't go back to it's original vast genetic state, because of that genetic information lost during selection.
so natural selection just SELECTS from the existing gene pool, it doesn't CREATE any new useful genetic information as evolution would require in order to be true
|Comment #1.1 by: matt on 11 Feb 2009, 05:53 GMT|
This person has no idea how molecular biology functions. A single nucleotide can copy incorrectly and cause a certain condition, such as in sickle cell anemia, however, it could also potentially mutate another nucleotide that would have some unknown, perhaps beneficial mutation. In addition, just because a gene MAY copy incorrectly during DNA replication, does not mean that it will. It does not always produce negative effects. Although sickle cell anemia may seem bad, in the context of evolution it makes sense. The populations most afflicted by sickle cell anemia have their genetic roots in areas where malaria is endemic. The misplaced nucleotide in this case, effects the hemoglobin gene. This mutation causes hemoglobin to be produced that misshapes the red blood cells in those afflicted into a sickle shape. This causes them to potentially form blocks and clots in the body. However, it also prevents the malaria parasite from living a part of its life cycle, which normally takes place on normal red blood cells in humans. Although the condition causes pain and sometimes death, it is not as bad as having malaria, hence those who possessed the mutant gene were more likely to pass it on, as those without it were more likely to die of malaria sooner and more frequently than those who had sickle cell anemia. Hence its presence today in those populations.So to summarize my example there, sickle cell might be seen to be a "bad" thing, but it simply was a random mutation that provided a benefit to the population that carried it. Genetics and molecular biology as we understand it today would not be possible without evolution. If you take insulin for diabetes, or any of the new slew of cancer drugs, you have scientists and their great understanding of biology, biochemistry, and especially evolution to thank for that.
|Comment #2 by: Sheldon on 13 Mar 2009, 07:04 UTC|| reply to this comment|
What if the human race is actually multiple races seeded here on planet earth; a product of DNA experiments preformed by extratrestrial beings? Could that explain some the the variances in DNA that we see between the different races and possibly lead to the question: where are the missing strands of DNA?
|Comment #3 by: Ashley on 27 Aug 2011, 05:42 UTC|| reply to this comment|
DNA differs among human races? No s--t! Freud, Boas, and the slew of cultural Marxists that emerged from the woodpile over the last century and a half have struggled to convince the world that race is a social construct with nothing less than rabid fanaticism. Questioning why this is would be very enlightening on this subject.
|Comment #3.1 by: bawls on 12 Nov 2011, 18:32 GMT|
we are not truly different races, we are all one race with differences resulting from ENVIRONMENT, you're very confused likely and seem to think all european/african/asian/etc. people are going to be equally similar or equally different, but I'd be willing to bet that if this is indeed true, that if you were to take the DNA of Danish person and the DNA of a Greek person, that their would be differences, because of the differences in ENVIRONMENT. So does that mean that every country contains a different race of people
|Comment #3.2 by: ASDF on 19 Nov 2011, 07:15 GMT|
Each country could indeed contain a different race of people. Countries can contain different subspecies of rhinoceroses, so why not people?
Obviously the DNA of a Dane and a Greek are going to contain some differences, but they will be more similar to each other than either would be to the DNA of an African.
|Comment #4 by: Ife on 15 Oct 2011, 11:32 UTC|| reply to this comment|
The genome project was focused on origins. The human race originated as one and because of changes in environment the physical bodies adapted dfferently. The 'new' research does not change the origins but it does look at the variety of changes over time. Ultimately race is a social construct for purposes other than medical break throughs.
|Comment #4.1 by: Homunculus on 25 Apr 2012, 07:33 GMT|
Race is certainly "not" a social construct. Only feeble minded loons espouse such outdated leftist nonsense.
Different races exhibit more then "taxidermic" differentiation, we react to medicines differently. Different races obviously look different superficially, but internally as well. Our bone structure is different, bone densities differ, skull shape, brain case molds, hair folicules differ for crying out loud.
Asian elephants are not different from African elephants because of "social constructs" they developed in the pachyderm herd. Asian elephants are different from their African cousins because they developed differentiation to deal with differing environments.
Im so sick of these idiots trying to infuse ideology into science. What IS ... IS, not what your silly little ideology wants it to be.
|Comment #4.2 by: Squirt on 14 Jan 2013, 22:56 GMT|
Finally, someone with some basic common since..Science is not what someone tries to make it..Science is what actually exists..
|Comment #5 by: reasonable mind on 16 Dec 2011, 21:47 UTC|| reply to this comment|
It's really 12% of the copy number variation that varies between races, not 12% of the DNA.
And racists, stop with the strawmen and whining about "race deniers", grow up and accept that human variation is minuscule when compared with variation between other ape species, and that Europeans are the closest relatives of Africans. If we try to make clusters or phylogenies without a large number of sequences, then it will all be a mess, people from Congo appearing to cluster with people from Norway and this sort of thing. Of course the picture of human migrations history gets clearer as more sequences are added, but still, most of your precious genome is shared with people from everywhere. Live with that.
|Comment #5.1 by: Homunculus on 27 Apr 2012, 01:34 GMT|
Dude ... quit trying to sound like you know what you're talking about. Because its obvious you haven't a clue. It doesn't make someone a racist to state FACTS and to communicate TRUTH. Thats what the quest of science is fundamentally all about ... a quest to expose TRUTH to the un-enlightened and to bring light to the darkness. Not to distort reality and obfuscate science to push an agenda or ideology.
Race exists dummy. With subjective eyes, with critical reasoning, with objective scientific experimentation. It doesn't help when people like you muddy the waters with distortions and chimerical wish fantasies.
Europeans are not the closest relatives of Africans, its the apposite, they are the least close due to genetic variation. Thats a fact. Its not racism, its a fact.
The genetic distance between an Englishman and a German is .002%, between an English and Japanese .061%, between an Englishmen and a Nigerian .133%, and between and Englishmen and a Chimpanzee 1.60%
To re-coin a phrase i just read ...live with that, and while you're at it learn to deal with facts for a change. Again ... your not helping.
|Comment #5.2 by: Mystic on 03 May 2012, 19:50 GMT|
It also says that it varies inside the same race as well.
|Comment #6 by: Homunculus on 25 Apr 2012, 07:14 UTC|| reply to this comment|
I think its absurd to think that 200,000 years is responsible for 12% variation CVN amoungst the races. Using that timeline we can look at the dna of the Sumerians (crack the bones and look at the dna in the marrow) and see a measurable spread to common man today. It doesn't jibe I'm not buying it. Something big is missing here.
|Comment #6.1 by: DM6 on 27 Apr 2012, 20:27 GMT|
Where are the sources to your claims? Plus watch this video from 4:25 and onward.
And lol at you using childish words like "dummy".
|Comment #6.2 by: DM6 on 28 Apr 2012, 04:36 GMT|
Go on YouTube and watch the video "Race Realism = Real Racism" from 4:25 and onward. Plus where are the sources to your claim?
|Comment #7 by: DM6 on 27 Apr 2012, 20:41 UTC|| reply to this comment|
Homunculus doesn't know what he is talking about nor has any sources to his claims.
4:25 and onward.
Race is a social construct. Deal with it.
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