Posted on 11/23/2006 7:09:00 PM PST by blam
Humans show big DNA differences
DNA comparisons: Gains (green), losses (red), the same (yellow)
Scientists have shown that our genetic code varies between individuals far more than was previously thought. A UK-led team made a detailed analysis of the DNA found in 270 people and identified vast stretches in their codes to be duplicated or even missing.
A great many of these variations are in areas of the genome that would not damage our health, Matthew Hurles and colleagues told the journal Nature.
But others are - and can be shown to play a role in a number of disorders.
To date, the investigation of the human genome has tended to focus on very small changes in DNA that can have deleterious effects - at the scale of just one or a few bases, or "letters", in the biochemical code that programs cellular activity.
And for many years, scientists have also been able to look through microscopes to see very large-scale abnormalities that arise when whole DNA bundles, or chromosomes, are truncated or duplicated.
But it is only recently that researchers have developed the molecular "tools" to focus on medium-scale variations of the code - at the scale of thousands of DNA letters.
Big factor
This analysis of so-called copy number variation (CNV) has now revealed some startling results.
It would seem the assumption that the DNA of any two humans is 99.9% similar in content and identity no longer holds.
THE DNA MOLECULE
* The double-stranded DNA molecule is held together by chemical components called bases
* Adenine (A) bonds with thymine (T); cytosine(C) bonds with guanine (G)
* These "letters" form the "code of life"; there are about 2.9 billion base-pairs in the human genome wound into 24 distinct bundles, or chromosomes
* Written in the DNA are about 20-25,000 genes which human cells use as starting templates to make proteins; these sophisticated molecules build and maintain our bodies
The researchers were astonished to locate 1,447 CNVs in nearly 2,900 genes, the starting "templates" written in the code that are used by cells to make the proteins which drive our bodies.
This is a huge, hitherto unrecognised, level of variation between one individual and the next.
"Each one of us has a unique pattern of gains and losses of complete sections of DNA," said Matthew Hurles, of the UK'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."
Evolving story
The new understanding will change the way in which scientists search for genes involved in disease.
"Many examples of diseases resulting from changes in copy number are emerging," commented Charles Lee, one of the project's leaders from Brigham and Women's Hospital and Harvard Medical School in Boston, US.
A microscope will show up the biggest code abnormalities
"A recent review lists 17 conditions of the nervous system alone - including Parkinson's disease and Alzheimer's disease - that can result from such copy number changes."
Scientists are not sure why the copy variations emerge, but it probably has something to do with the shuffling of genetic material that occurs in the production of eggs and sperm; the process is prone to errors.
As well as aiding the investigation of disease and the development of new drugs, the research will also inform the study of human evolution, which probes genetic variation in modern populations for what it can say about their relationship to ancestral peoples.
Fascinating. Thanks.
Most interesting.
FOXP2 is probably only one of many genes that are crucial for speech development. FOXP2 is nearly identical in every human being who has normal speech development. This gene was identified by studying a family who had inherited speech difficulties. A brief layperson's review of this gene is here. An excellent, but more technical review of this gene is here.
The fascinating aspect about this gene is that it is found in organisms ranging from fungus, to flies, to primates, to humans. However, the human variant of this gene is significantly different than primates. The primate version is closer to that found in mice, as compared to humans. Scientists estimate this gene underwent genetic mutation in humans 100,000 to 200,000 years ago-- about the time archaeological evidence suggests humans began using language.
Our ancestors who carried this "mutation" would obviously have a huge survival advantage over other members of the species who did not have it.
?
Pre-ORDAINED??
Scientists have shown that our genetic code varies between individuals far more than was previously thought. A UK-led team made a detailed analysis of the DNA found in 270 people and identified vast stretches in their codes to be duplicated or even missing.That much isn't news. :') There are loads of so-called junk DNA, which doesn't seem to code for anything, and may have been spliced in by virus infections long ago. Or perhaps it relates to a lack of meaning in nuclear DNA. ;')
It would seem the assumption that the DNA of any two humans is 99.9% similar in content and identity no longer holds... "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.And that's true regardless of race, creed, color, or national origin. ;') [rimshot!] To all -- please ping me to other topics which are appropriate for the GGG list. Thanks.
Please FREEPMAIL me if you want on or off the
"Gods, Graves, Glyphs" PING list or GGG weekly digest
-- Archaeology/Anthropology/Ancient Cultures/Artifacts/Antiquities, etc.
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The Scars of Evolution"The most remarkable aspect of Todaro's discovery emerged when he examined Homo Sapiens for the 'baboon marker'. It was not there... Todaro drew one firm conclusion. 'The ancestors of man did not develop in a geographical area where they would have been in contact with the baboon. I would argue that the data we are presenting imply a non-African origin of man millions of years ago.'"
by Elaine MorganBenveniste, Raoul E. and Todaro, George J. (1976) Evolution of type C viral genes: Evidence for an Asian origin of man. Nature, 261:101-107. This study also applied DNA hybridization to the apes. They found a 3-way split.
Primary Literature
by Jonathan Marks
Especially that claim about inventing the wheel..
Everybody knows neanderthals didn't invent the wheel..
Except Al Gore..
Maybe that was one of Gore's ancestors..
Over 95 percent of DNA has largely unknown function
Presently, only the function of a few percent of the DNA is known, the rest has been believed to be useless garbage, commonly called "Junk DNA" by molecular biologists.
Increasing evidence is now indicating that this DNA is not "junk" at all. Especially, it has been found to have various regulatory roles. This means that this so-called "non-coding DNA" influences the behavior of the genes, the "coding DNA", in important ways.
However, the knowledge is still very incomplete about this DNA. And there is little knowledge about the relationship between non-coding DNA and the DNA of genes.
Without this knowledge it is completely impossible to foresee and control the effect of artificial insertion of foreign genes.
This is a very important reason why genetic engineering is unsuitable for commercial application. It is still at a stage of early experimentation with very incomplete understanding about its consequences. According to the ethical standards of sound science, the products of such experimentation should be strictly contained in laboratories, especially as released DNA may spread indefinitely in an uncontrollable way.
[Excerpt]
http://www.psrast.org/junkdna.htm
If it didn't convey some advantage for us we wouldn't still have it, would we?
One can barely understand how Darwin popularized evolution when people thought cells were fairly uncomplicated but HOW can anyone possibly believe this anymore when we read ""letters" form the "code of life"; about 2.9 billion base-pairs in the human genome wound into 24 distinct bundles, or chromosomes". This being just one aspect of the fathomless intricacy of genetics. It's like believing all the books in the world somehow wrote themselves and this is a very, very simplistic example. Believing that everything just happened (and survival of the fittest does not change this, it's just a part of it)in a thoughtless material universe should be impossible unless something is obviously really blinding people..... Maybe it's something in or better yet, missing from their genes;>)
Mutations arise; also there are viruses. There isn't any advantage to any of it, only the occasional disadvantage -- and that's only supposition. :')
The possible DNA combinations are, 4 x
4,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000
It is said that any number larger than 2 x 10 to the 30th power cannot occur in nature. Yet you will believe with the faith of a religion.
Dixon and Webb calculation, on page 667 of their standard reference work.
“In order to get the needed amino acids in close enough proximity to form a single protein molecule, a total volume of amino-acid solution equal to 10 to the 50th power times the volume of our earth would be needed!. That would be a bowl of solution bigger than our earth, the earth would fit in it. Yet you will believe with the faith of a religion.
The possible arrangements of 20 different amino acids are, 2,500,000,000,000,000,000 possible arrangements. That in itself is a large number, not as large as above.
If evolution is true than every protein arrangement in a life form had to be worked out by chaotic random chance until it worked right. First one combination then another, until one was found that worked, but the organism would have been long dead, if ever alive.
The probability of forming 124 specifically sequenced proteins of 400 amino acids each by chance is 1 x 10 to the 64489 power. Yet chaotic random chance can do it.
The odds are so impossible that even the simple beginnings could not have happened by chance. Yet evolutionist will hold to their religion {nothing created everything} with dogmatic fervor as strongly as anyone who believes in God as their creator.
Not really - what does your appendix do?
Certainly very intelligent design.
That's why evolutionists hate math, and particularly probability and statistics.
Isn't any difference in genetics between individuals evidence of evolution (according to evolutionists)?
Kind of a low-threshold definition, if you ask me (change in allele frequency)....
found a link to this old topic (2002) in someone's links page:
UGA Study of Retroviruses Shows Human-specific Variety Developed When Humans, Chimps Diverged
The University of Georgia news bureau | Thursday, August 1, 2002 | Phil Williams
Posted on 08/02/2002 2:44:30 PM EDT by forsnax5
http://www.freerepublic.com/focus/news/726668/posts
ATHENS, Ga. — Scientists in the past decade have discovered that remnants of ancient germ line infections called human endogenous retroviruses make up a substantial part of the human genome. Once thought to be merely "junk" DNA and inactive, many of these elements, in fact, perform functions in human cells.
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