Friday, April 11, 2008

Gene genies.

There's a story going around about Russian scientists who have worked out what 'junk DNA' does.

Junk DNA is what you might call moulding flash, leftovers, spares. It doesn't do anything that anyone's been able to determine. There's an awful lot of it.

These Russian scientists have 'proved' that this junk DNA does everything from telepathy to faith healing.

So why don't I believe it?

DNA doesn't actually do anything. It codes for proteins, and that's all. It's the instruction book for the cell. The proteins made from this template can be enzymes or parts of cell structures, but the DNA itself doesn't do anything.

Expecting DNA to be active on its own is just like sitting on the instruction manual for a car and expecting to go somewhere. DNA isn't active. It's the book that tells you how to build and fix the vehicle, it's not the vehicle itself.

Another reason I don't believe it is that the article is dated 2005, but none of the things it claims to have achieved have ever appeared. None of the examples of paranormal events given in the article have been shown to involve DNA. There's no logical reason to assume DNA does anything aside from determining the shape, function and various colours of your body. DNA is purely in the physical world.

Changing your DNA will not allow you to change into a werewolf. It's more likely to cause cancer. To keep the car analogy, if you take the manual out of a Ford and replace it with a manual from a Lexus, your car won't change into a Lexus. All that will happen is this: the next time you try to fix your Ford using your Lexus manual, you'll break it.

These Russians might be real scientists, I don't know. If they are, then they are proof that we still have a healthy population of mad ones.


tom sheepandgoats said...

Changing your DNA will not allow you to change into a werewolf. It's more likely to cause cancer.

I've long thought this must me a fatal flaw to evolution, and am surprised I don't hear it mentioned more often. I don't really keep up with "IS" literature, though. Perhaps it is.

If evolution is driven by mutation and if, as we're told, beneficial mutations are dwarfed in number by "junk" mutations, then in would seem that the junk would accumulate and more than offset the benefits of the good stuff.

Does that make sense?

Romulus Crowe said...

Hi Tom

Well, it doesn't stop evolution, but most DNA changes are detrimental. There's one school of thought that says the junk DNA is there to act as a buffer - damage by UV etc is less likely to hit important parts if those parts are surrounded by unimportant junk. Sort of like surrounding your small military base with miles of empty sheds that look the same.

Hits on the important parts are almost always bad, but once in a while the change either won't matter (say, eyes turn out to be blue instead of green) or won't be too detrimental (as in my case, where the genes for colour vision don't all work). Once in a very long while, they'll produce a change that's useful although it might not be immediately obvious.

Say someone's born with the ability to go without drinking water for long periods. They might go through their lives without ever noticing they can do it because they don't need to.

If there's a drought, this person has an advantage - and the longer the drought goes on, the better this person will do compared to the rest of us. if the drought goes on long enough, only people with that mutation would survive. Unfortunately, in this example, he's the only one. So it's not much help.

However, if there's no drought, the guy never knows he's droughtproof, he gets married and has kids, they have kids... a way down the line there's a whole family who are droughtproof and they don't know it. Until there's a drought.

Then, there are a whole bunch of people who can survive a long drought. They don't look any different yet, but give it a few thousand years where these pople live isolated from the rest of the world (because they live in a place nobody else can live in) and differences start to accumulate.

Eventually they can't interbreed with other humans. At that point, they're a different species.

Evolution makes changes, and it happens all the time. Natural selection (which isn't the same thing) is what makes those changes obvious.

You might know someone who can drink alcohol and never get drunk. Someone who can start and stop smoking at will because they never get addicted. Someone who can live on burgers and chocolate and never get fat. Someone else who lives on salad and puts on weight anyway.

They're all differences caused by little differences in genetics, but they don't matter in the modern world. They aren't make or break differences.

Unless the food runs out - then the guy who's better at storing food as fat will be laughing.

But I've never seen why religion is so against evolution. It doesn't disprove intelligent design. In fact, an intelligent designer would make his creation adaptable to changing conditions, surely? Especially if he knew how those conditions would change.

I doubt we'll see any dramatic changes in the human form. Humans have a tendency to force the environment to suit themselves, rather than the other way around.

The funny thing is, evolutionists are trying to prove evolution happens while conservationists are doing their best to make sure it stops.

Even science has its factions!

tom sheepandgoats said...

Well, maybe. But it seems odd to me.

Can it really be that the beneficial mutations actually bring benefit, while the far more numerous harmful mutations do no harm?

It seems more likely to me that by the time drought conditions materialized to favor the drought-gene guy, he would have been tripped up many times over by an accumulation of harmful mutations. Thus, he would not have survived to reap dividends from his beneficial drought mutation.

Is that argument unreasonable?

Romulus Crowe said...

A reasonable assumption, Tom, and a common mistake.

It's true that for every beneficial mutation there are millions of harmful, worthless or inconsequential ones, but they don't all happen in the same person or even in the same body cell.

For the sake of example, let's ignore everything but beneficial mutations and fatal ones. If we assume that one in a million mutations is beneficial, then 999,999 are fatal. So if it happened to one person then they'd get a useful change to their DNA but they'd be very dead before they could use it. Fortunately, that's not how it goes.

It's more like this - you take a million people and they get a mutation each. In this (rather extreme) example, one gets a benefit and the rest die.

Or more accurately, a million body cells - one gets the mutation and the rest are killed. A million isn't many as long as they don't all die at once, in one place, and cause a necrotic spot. that wouldn't be pleasant. it does happen like that if you get a radiation burn though.

Let's say the mutation changes the eye colour gene from green to blue. The green-eyed person doesn't change the colour of their eyes because their irises are already built. The mutation is only in one body cell, too, and it might not be anywhere near an eye.

Ideally, it's in the cells that form eggs or sperm. That way, the mutation gets passed on to a child who then has blue eyes.

See, the mutation can't change a body that's already been built. Only one cell has this mutation and if it's not in the reproductive organs, then it's a dead end. Mutations in completed bodies don't show unless they cause cancer.

For a mutation to work - for, say, all your body cells to be resistant to low water intake - that mutation must have been in place at conception. It has to have been in either the sperm or the egg. Then, the newly built body has the new characteristic throughout.

Again, most such mutations are bad (those caused by thalidomide are a prime example) but once in a while, there can be a useful one. A bigger brain, more efficient lungs, anything that allows that individual to prosper increases their chances of passing on the characteristic to their own children.

Useful mutations are rare - but even if we say there are no more than one in a billion, that would mean there are six on the planet right now.

The next step would be natural selection. If one of those mutations gives an advantage in a particular environment, then that individual will be more successful than the others and will pass that characteristic on. If it doesn't give an advantage in that environment it won't be noticed at all.

It works like this in animals but humans are a special case because we tend to treat anyone different as a freak. So, if anyone was born with gills, instead of making a massively successful career as a diver and spawning a population of amazing aquatic humans, they'd end up in a cage or a laboratory. Or a hospital, having those unsightly slits sewn up.

I doubt the human race will change form any time soon. We just won't let it happen.

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