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Breakthrough In Human Genetics
Many readers have submitted this story about a breakthrough in our understanding of human DNA: in particular, how much variation can exist between peoples' genes and how genes are involved with certain diseases. "One person's DNA code can be as much as 10 percent different from another's, researchers said on Wednesday in a finding that questions the idea that everyone on Earth is 99.9 percent identical genetically.
They said their new version of the human genetic map, or 'book of life,' fills in many missing pages and chapters to explain how genes are involved in common diseases.
The Human Genome Project mapped the billions of letters that make up the human genetic code. Scientists later refined the map by looking for single variations called SNPs or single nucleotide polymorphisms.
The CNV map gives researchers a different way to look for genes linked to diseases by identifying gains, losses, and alterations in the genome."
i remember reading that humans and chimps are 98% the same
and previous to this announcement, all people were 99.9% the same
the implication here is that people are actually as low as 99% the same
which means one crazy ass inference:
it should be possible to find two people and a chimp such that and person A is equally different from the chimpanzee as he is from the person B
no way
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
"One person's DNA code can be as much as 10 percent different from another's, researchers said on Wednesday in a finding that questions the idea that everyone on Earth is 99.9 percent identical genetically." It doesn't call it into question at all. The simple matter is that how you define "different" and measure the percentages makes a big difference. The human genome is ~3 billion base pairs. You can have a singe nucleotide change in a gene of say 5000 base pairs. When you compare a given gene between individuals, do you count the whole gene as being entirely different? Or do you say that it is 99.98% (4999/5000) the same?
Does anyone know what stance our major religions have on DNA? For example, how should a true Christian receive this news?
I know it's not entirely on topic, but seeing that the bible describes humans as flesh and blood and as one, it would be interesting to see what this up-to-ten-percent-difference would put science against religious belief.
Full Tilt
That 10% is way off. There is on average a variable base (across all people) every 300 bases. So by my calculations, people are at least 1 - 1/300 = 99.7% similar. Not everyone can be different everywhere so that gets us back in the 99.9% territory. The copy number variation map has not changed those numbers that much...
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Even if two genomes are 100% the same, that doesn't mean that the products of each will be the same.
Why? Gene expression can differ depending on environmental factors.
As a simple analogy, your DNA = a cookbook. While many recipies are cooked automatically by the systems in your body, other recipies are cooked or not cooked depending on the environment in which the organism finds itself.
I haven't read a good article on gene expression, really. Various mechanisms are alluded to in the literature, but it seems to be unclear how gene expression is or is not triggered. More specifically, researchers seem to know that this particular mechanism turns a given gene on or off, but how that mechanism is triggered is unknown (or not the focus of the article/research).
Also, I'd guess that environmental gene expression stars in the womb - that the fetus gets clues to the external environment from the nutrients and chemicals coming from the mother and adjusts itself accordingly. You could test that by somehow getting ahold of some in-vitro twins and implanting them at different times, I guess? But there probably still would be too many variables.
Humans have escaped the phenomenon of Natural Selection, for the most part.
All of us who wear glasses? We should have been culled. All these people developing diabetes from eating too much sugar? Selected against. Asthma? You get the picture.
Running with the idea that there is a higher power that created the world, I would say that Natural Selection is the method that higher power uses to figure out what works. But now with health care and a strong sense of altruism, errors in the genetic code are propagating throughout our species and wrecking havoc. In other words, we're playing god by saving lives that should have been selected against and allowing them to pass on their flawed genes.
I also contend that if we were created by a higher power, and that higher power enabled us with the ability to modify our genetic code, then it is our right (nay, our duty) to do so; otherwise, we would lack this ability. I believe that we should selectively erase genes which cause a predisposition to things like Down Syndrome or diabetes or cancer, etc. This would effectively select against all detrimental mutations.
This could also be the limit of Natural Selection as it tends toward infinitely fast; beneficial mutations in one human (for instance, the HIV resistance that elite supressors have) could be propagated throughout the species' genetic code in a single generation.
Perhaps I should leave you with an example, one that even a Christian might be able to tolerate. Imagine a future where you and your s/o collect your eggs and screen them for genetic defects, like Down Syndrome. Once a viable egg has been found (and you don't have to look up what the hair color or eye color will be, you could just leave that to fate), start screening some sperm. Produce a viable fetus which will grow up to be healthy.
Now imagine that you were one of those people who didn't do that for your kid. And now your kid is born with a gene that means they're 80% likely to die from some horrible disease by the age of 30. If I were that kid, I would be pissed at my parents for not choosing the screening option.
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From the article in the Independent referenced elsewhere in this thread:
o logy/article2007490.ece
http://news.independent.co.uk/world/science_techn
"The scientists looked at people from three broad racial groups - African, Asian and European. Although there was an underlying similarity in terms of how common it was for genes to be copied, there were enough racial differences to assign every person bar one to their correct ethnic origin. This might help forensic scientists wishing to know more about the race of a suspect."
In short, this research supports the notion that race is a useful and scientifically supported concept. Indeed, virtually all new data coming in on human genetic differences go against the fashionable yet not-very-well-supported notion that "race does not exist". How strange.