The intricacies of human DNA alone are evidence enough of a designer.
To be honest, while I acknowledge that information is on DNA, perhaps it is just sticky-tape for information. It may be that information nuggets just stick together intrinsically and DNA is but an example of such information superpositions.
Here's an interesting article I found:
What We Have in Common with Flies: A Lot
Scientists are discovering that plants, animals, and yes, humans, are astonishingly similar genetically. That's not bad news
When scientists first began cataloging genomes -- the genetic code written in DNA that describes the characteristics of a living creature -- it seemed certain that the map of the human genome would appear unique from those of any other creature. But research is highlighting just the opposite: how much alike the thousands of different species of plants and animals on earth are. And scientists are surprised at how often the similarities track in unexpected ways.
Start with the idea of human races. In 1998, Alan R. Templeton, a professor of biology at Washington University in St. Louis, Mo., combed the DNA of different global human populations for racial differences. His results showed that 85% of genetic differences in the human DNA were due to individual variation, and a mere 15% could be interpreted as "racial." That figure is two or three times below the threshold biologists use to define race in other animal populations. "Race is a real cultural, political, and economic concept in society, but it is not a biological one," observed Templeton.
While there is plenty of genetic variation among humans, all humans share the same genome. Human differences, it seems, are more determined by the 97% of the human genome that doesn't carry the code for genes. Once referred to as "junk" DNA, it contains those sequences that determine which genes are active -- and when.
FIDO'S FIX. Indeed, Templeton found more genetic similarity between Europeans and sub-Saharan Africans and between Europeans and Melanesians (inhabitants of islands northeast of Australia), than there is between Africans and Melanesians. Yet sub-Saharan Africans and Melanesians share the dark skin, hair texture, and cranial-facial features commonly used to distinguish humans by race. "Humans are one of the most genetically homogenous species we know of," Templeton concludes. "The between-population variation is very, very minor."
Man's best friend, the dog, is in a similar fix. All canines belong to one species and share a common genome. Genetically, there are insignificant differences between a timber wolf and a Scottish terrier. But Rover, with his high reproductive rate and short lifespan, has had his individual variation manipulated by being bred in closed populations.
That's why researchers at the Fred Hutchinson Cancer Research Center in Seattle and Cornell University's College of Veterinary Medicine began making genetic maps of various breeds of pedigreed dogs in the mid-'90s. Inbred dogs share a host of genetic diseases, including cancer, epilepsy, retinal degeneration, bleeding disorders, and skeletal malformations, with humans. But finding a genetic basis for those diseases is dificult in the mix of human diversity. Their goal: find the genes in a purebred canine, then look for similar ones in humans with the same disease.
SPRY OLD CHIMPS. Humans' closest cousin in a separate species is the chimpanzee, which is 99% genetically identical. But that tiny difference is striking. Chimps infected with the HIV virus don't get AIDS. Instead, the virus lives in peaceful symbiosis with the chimp's immune system. Nor do they develop Alzheimer's disease, despite sharing a gene that confers high risk for Alzheimer's in humans.
In addition, cancers such as those of the breast, lung, and prostate are rare in apes, occurring in less than 2% of their population, compared to more than 20% in humans. To find answers to this puzzle -- and possibly cures -- Ajit Varki, a geneticist at the University of California, San Diego, published an urgent call to launch a Chimpanzee Genome Project last August in the journal Genome Research.
Yet, other organisms -- insects, not chimps -- seem have share our propensity for disease. The most unfortunate creature so far is the lowly fruit fly, known to scientists as Drosophila melanogaster. In 1916 this tiny bug offered the proof that genes are located on chromosomes in the nuclei of cells.
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"The higher complexity in animals comes without needing a lot of new parts"
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Scientists from the University of California at Berkeley and Celera Genomics in Rockville, Md., churned through Drosophila's genome, publishing the sequences of its 13,601 individual genes last March in the journal Science. It was the largest entire genome sequenced before the human project was completed. When the researchers compared the fruit fly genome to the human one, they found that of 289 human genes implicated in diseases, 177 closely matched genes in D. melanogaster, including those that play roles in birth defects, cancers, immune-system disorders, and kidney, blood, and neurological diseases.
The scientists were also surprised to learn that the flies had only twice as many genes as yeast, a simple, single-celled fungus. "It takes only twice as many genes to make an animal that can fly around without crashing into walls, has tissues, nerves, muscles, memories, and other kinds of complicated behaviors," noted Gerald Rubin, who heads the Berkeley Drosophila Genome Project. "The take-home message is that the higher complexity in animals like flies and humans comes without needing a lot of new parts."
FIRST CODEBOOK. "The underlying biochemistry of fruit flies and humans is remarkably similar," adds Roger Hoskins, who headed the gene-mapping effort at Berkeley. So too, is the genome of a tiny worm that is also a favorite of geneticists. When the genome of Caenorhabditis elegans was decoded in 1988, it stood as the first time researchers had spelled out the instructions for a complete animal.
Even though they are so small several can fit on the head of a pin, the roundworm has nervous, digestive, and reproductive systems similar to those of higher animals. The 97 million DNA subunits in its genome (compared to 3 billion in a human) contained 19,099 genes. Among the surprises C. elegans yielded: It has many more genes than the geneticists had suspected, and 40% of them matched those of other organisms, including humans.
We may also be a lot like what we eat. The genome of cows hasn't been completely sequenced, but a team of investigators from the University of Illinois, Urbana-Champaign, and Texas A&M University recently reported in Science a comparison of cattle genes to the human genome.
MILLIONS OF YEARS APART. Out of 768 known genes, 83% are identical to those in humans. Moreover, many of those genes appeared in the same position on the same chromosome as they do in humans. Four entire chromosomes appear to have the same genes in both species -- despite man being separated from cattle by more than 60 million years of evolution. When the entire genomes of cows and humans can be compared, the data will have "enormous scientific and practical significance in food safety, animal health, and the competitiveness of our domestic beef and dairy industries," says Harris Lewin of the University of Illinois, who led the research effort.
It may not take long. Sequencing C. elegans took eight years to complete. But, using a fast, new technique invented by J. Craig Venter of Celera, researchers raced through Drosophila in six months. And Venter followed that by roaring through the enormous human genome in just six months, completing the task in April.
Now, Celera's instruments are racing through the mouse genome. This project has enormous implications because hundreds of specially bred varieties of these rodents are critical to medical research, both to test new drugs and as models for human disease.
UNKNOWN GENES. So what once seemed inconceivable now looks like it will be realized in just a few years: the complete parts list for all living creatures on earth. This immense encyclopedia of genetic data -- call it the Whole Genome Project -- will allow researchers to trace evolution back to the oldest, most primitive organisms on earth and provide medical researchers with important new tools for treating disease. Moreover, each genome deciphered so far shows a small number of unknown genes. Further study will tell us what they do, which could explain why chimps don't get AIDS, for example.
The data will also show what makes a human different from a mouse, or a sea slug from a shark. But the larger message is a final scientific affirmation of a very old idea: All plants and animals on earth are truly related. That's life.
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