"Will DNA Prove to be the Life Code Throughout the Universe?"

Neil deGrasse Tyson believes that BIG question of the 21st century is will we discover life somewhere other than on Earth? He views it as an "unimpeachable first goal" in our exploration of the cosmos.

And what most fascinating is the question of whether that life has DNA. It's  fascinating, Tyson says, because either DNA is inevitable as the foundation for the coding of life, or life started with DNA in only one place in the solar system and then spread among the livable habitats through panspermia. Microbial life can land on and seed another planet, thereby not requiring that you have to create life from scratch multiple times and in multiple places.

Another totally intriguing possibility, one of many that deGrasse Tyson Director of the Hayden Planetarium at the American Museum of Natural History and host PBS's NOVA scienceNOW., describes in Origins: Fourteen Billion Years of Cosmic Evolution, is that there is life that has encoding that has nothing to do with DNA.

It is the relentless shifting and mutating of DNA, says Dennis Overbye in a brilliant essay in The New York Times, that generates the raw material for evolution to act on and ensures the success of life on Earth (and perhaps beyond). Dr.Paul Davies co-director of the Arizona State University Cosmology Initiative said that he had been encouraged by the discovery a few years ago "that some sections of junk DNA seem to be markedly resistant to change, and have remained identical in humans, rats, mice, chickens and dogs for at least 300 million years."

But Dr. Gill Bejerano, Assistant Professor of Developmental Biology and of Computer
Science at Stanford, one of the discoverers of these “ultraconserved” strings of the genome, said that many of them had turned out to be playing important command and control functions.

“Why they need to be so conserved remains a mystery,” Berjerano said, noting that even regular genes with known functions undergo more change over time. Most junk bits of DNA that neither help nor annoy an organism mutate even more rapidly, Overbye points out.

What your quess: Is the DNA the cosmic code for life in the universe, or is it possible that there's are alien, unknown foundations? At the Galaxy, we place our chips on DNA.

Posted by Casey Kazan.

http://www.pbs.org/wgbh/nova/origins/tyson.html
http://www.nytimes.com/2007/06/26/science/26DNA.html?_r=2&oref=login&oref=login

Image Credit: Copyright Jimmy Turrell

Comments

[Francis Kingz]

It is not a question that can be answered. Not enough information is available and it will not be available until alien life is found outside our solar system and studied.

Even if life was found elsewhere in our solar system and was determined to be DNA based this would not resolve the question. All of the planets are too close together, relatively speaking, and life could have been spread from one to the other by asteroids impacting the planets and moons and the ejecta being transferred by meteor impacts.

My personal guess would be have to be no, all life in the universe is not DNA based.

Our galaxy alone contains over 200 billion stars. It has been calculated that there are at least 100,000,000,000 galaxies in the universe. Estimates are that there at least 1,000,000,000,000,000,000,000 stars in the universe.

I think it would be arrogant of us to assume that in all the vast reaches of space the way life has evolved on this planet is the only way possible for life to evolve.

Throughout history people have always mistakenly assumed that we are unique and important to the universe. Not that long ago it was believed that the entire universe revolved around the earth. Billions of superstitious(religious) people still believe that a god created the entire universe just for us.

Our planet is an insignificant little speck traveling around an unremarkable star on the outer edge of an average galaxy. I find it very hard to believe that our form of life is the only form of life possible. What would be the odds of that? Astronomical?

One question though about this quote: "that some sections of junk DNA seem to be markedly resistant to change, and have remained identical in humans, rats, mice, chickens and dogs for at least 300 million years."

Um. Humans, rats, mice, chickns and dogs have been around for 300 million years? I believe mammals, period, have not been around anywhere near that long.

[SusanGrisantiGuitarist]

Since the Universe is consistent with stars & galaxies & dark matter, then it's logical that it's consistent throughout with DNA, in my most humble opinion...
Aliens that are made of tissue similar to humans would probably have DNA...but aliens that might exist in another dimension would not require DNA...time will tell

[bumpy]

If the same "junk" DNA is found in many diverse types of mammal and even birds today, the implication is, first, that it already existed in more primitive life forms long ago that are ancestral to all mammals and birds; and second, that it is not junk but has some important function not yet known.

[bumpy]

Continuing, if I may -- Our present system of inheritance, based on both nucleotides and proteins, is exceedingly complex and therefore probably not the first that evolved on Earth. That it is now the only system on Earth may well be the outcome of competition among several earlier, simpler systems. The competition might conceivably have had a different outcome here, and may in fact have other other outcomes elsewhere. IMHO

[Basuto9]

Neither I, nor any of my relatives (as far as I know) were around 300 million years ago; does the author possibly mean something else re 300 million years? And the DNA question is just another one to speculate on - it is, or it isn't, and right now we don't know.

[TJ]

Neil; may be on to something the universality of design of the universe...

For my money in the future it will become more and more clear that the Universe as we know it, is a Life Factory, it's very design and purpose is to create life..!

There's life all over the universe and even our Galaxy but the distances involved are beyond our real comprehension or ability to surmount them...