Bio-informatics

This article is about the Principles of Bio-Informatics, as in DNA editing (genetic engineering), etc. It isn't similar to other forms of genetic engineering and is more about benefits, and mapping of the genome, than ethics or real research.

Mapping the DNA

As a modern state-of-the-art human, you are made up from trillions of cells, but when you were first conceived, you were just one single cell. Along the way, you grew two arms, two legs, two eyes, one liver, and so on. The blueprints, or instructions, for all your body parts were contained in the DNA in that single fertilised cell. These instructions still exist in every cell in your body - except for your red blood cells.

Now consider the all-too-familiar scene that you see on the roads - the driver with one arm illegally hanging out of the window. Every now and then, the arm gets scraped off by a vehicle going the other way. In many cases, the driver has to wear an artificial arm. But back in the uterus just after they were spawned, the driver grew a right arm, and the instructions on how to grow that right arm are still there in the DNA. Wouldn't it be wonderful if we could find those instructions in the DNA, and activate them, so that the driver could grow another arm. After all, if the salamander can grow a new limb, why can't we?

We need to understand our human DNA better. It's a collection of atoms, which are arranged to look like a long ladder, with rungs joining the side rails. The DNA is all coiled up very tightly to fit inside each cell, but if you were able to tease it out, it would be a few metres long.

There are three billion rungs in the DNA ladder of life, but these rungs are not all identical. There are four different rungs, which we call either A, C, G or T. One great discovery was that a set of three rungs contains the information to make one amino acid. So the set of rungs AAA will make one amino acid, while the rungs ACG will make a different amino acid. When these amino acids join together they make proteins, and these proteins can speed up chemical reactions. And finally, these chemical reactions make flesh and skin, blood and bone, brain and liver - and everything else you need for a new human being.

At the moment we have mapped almost 100% of the human DNA, and at the current rate of progress, we should have mapped it all by around the year 2007. Then we can go looking for the small section of the DNA that holds the instructions as how to grow a new arm. It's not as far-fetched as it sounds. By October 1995, molecular biologists had found the section of the DNA of the common fruitfly, that controlled the growth of its eyes. They learnt how to switch it on, and they ended up with a fruitfly with 18 eyes! It's early days yet, and the molecular biologists have a lot to learn before we can grow a human arm as reliably as a salamander can grow a limb.

But there's another hurdle to jump. The DNA is huge! If there was a book listing all the 3 billion rungs of the DNA, it would take you 30 years of your life just to read it. It would take even longer to understand it all. That's why a new science of bio-informatics has been invented. It's a combination of computer science, biology, chemistry, physics, cryptography, molecular biology, and a whole bunch of bio-medical subjects.

According to Wired magazine, graduates in bio-informatics are getting up to $100,000 US per annum. It took us less than 70 years from the first flight in an aeroplane, to the first joyride to the Moon. How long before the first natural regrowth of a limb? It might not just be a divinity that shapes our ends - but our DNA as well.

What you can do with DNA, and how

Different bits of the DNA do different things.

If one tiny part of the DNA is activated, it triggers the growth of cells that dump carbon dioxide and pick up oxygen - lung cells. If you activate another tiny part of the DNA, you make a structure that is, weight for weight, stronger than steel, and self-repairing - bone.

The orthopaedic surgeons call bone "The Prince Of Tissues", because it heals so beautifully. But bone has another magnificent characteristic. It continually destroys and rebuilds itself, and continually replaces its calcium atoms with new calcium atoms.

You don't get a letter from your local hospital every seven years-or-so asking you to admit yourself into hospital to have your 200-plus bones removed, and replaced by a different set of 200-plus bones. No, your bones rebuild themselves "on the run", while you're still using them. Imagine being able to do this trick.

Firstly, the key to the genetic revolution will be the "mapping" of all of the human DNA. What exactly does this mean?

The human DNA molecule looks like a very skinny, 5-metre-long ladder - two side rails and a whole lot of rungs. Your average ladder has about 10 rungs, but the human DNA has about 3 billion rungs. Each rung can be of one of four different types.

To "map" the DNA means to know what each of those rungs is. But surely the DNA is very different from person to person?

No.

There is very little difference between a black pigmy African woman and a big, blonde bloke of a Scandinavian, as far as their DNA is concerned.

First, the man-woman difference. DNA is usually neatly bundled up into 46 little packets, called chromosomes. The only difference between men and women is that women have an X chromosome, while men have a Y. A "Y" is just an "X" with one of the arms missing. So women (with the X chromosome) are the luxury model with all of the options, while men (with the Y) are the cheap economy model. But even so, the difference between men and women is very small.

The difference in skin colour is another very minor point. Skin colour comes from the melanin in your skin - more melanin means a darker skin colour. This melanin is made by cells called melanocytes. All humans have roughly the same number of melanocytes. It's the activity of the melanocytes that makes the difference between a Scandinavian and a dark-skinned person. In the fair-skinned Scandinavian, the melanocytes are mostly asleep, while in the dark-skinned African, they are mostly running flat chat.

The third main difference is height. But once again, this difference is very minor. Your final height depends upon on how much growth hormone is squirted into your body at different times in your life. Growth hormone comes from the pituitary gland in your brain. But the short Pigmy's pituitary gland releases tiny amounts of growth hormones, while the tall Scandinavian's pituitary gland pumps out heaps.

The difference between our black Pygmy woman and our tall pale Scandinavian man is less than the difference between a red Ferrari, and a blue one. But their kidneys, hearts, lungs, muscles, pancreas and so on are almost identical In fact, one lesson that we have learnt from genetic engineering so far is that the differences between us are much less than our similarities.

In not time at all, we will have the "map" of the DNA of the average human. But we won't know which bit says to grow a pancreas, and we certainly won't know how to make it grow a new pancreas.

Some people talk about the evils of some aspects of genetic engineering, where a clone of you will be grown so that it can be later "harvested" for a replacement pancreas (eg, to cure diabetes). (For some body parts, such as the heart, the "harvesting" would, of course, kill the clone.) This is a ridiculous way to get a new pancreas. In the pathway that they envisage, your DNA will replace the native DNA of an-already fertilised egg, which will then be implanted into a friendly uterus (already we are running into ethical problems). The egg then spends nine months growing into a baby, and then another 20 years growing into an adult, at which time the pancreas is supposedly removed and the adult somehow "got rid of".

This is murder, and extremely stupid as well.

Why wait some 20 years for your transplant pancreas!?!

Surely it would be much easier to learn the trick that bone uses, and re-grow your diseased pancreas into a healthy pancreas on the run. This would happen over the period of a few months. After all, if you're really desperate for a pancreas, you could be dead long before your replacement pancreas, being grown in your clone is ready to take away.

Genetic Revolution

In the old days there was no cure for diabetes.

Then we discovered that the pancreas made insulin, and that some types of diabetes could be held at bay by frequent injections of insulin. But back then, the insulin came from the pancreas of the pig - and pig insulin is slightly different from human insulin, so that there were a few side effects.

The First Stage of the Genetic Revolution is to modify a living creature so that it makes a chemical we want. Today, diabetics can buy, from their local chemist, genuine human insulin. This insulin is not made by squashing up human beings, but by genetically-modified bacteria that live in vats and make the insulin hormone for our use. We have already successfully done this.

The Second Stage of the Genetic Revolution is to grow an organ - outside the body. We have already successfully grown, in a laboratory dish, the bladder of a dog. This bladder was grown from a few cells. It is difficult, but a skilled surgeon could transplant this bladder into a living dog. So far, we have not successfully grown a human pancreas (an organ much more complicated than a bladder) - but we will, maybe in 10 or 20 years or so. The operation to transplant a lab-grown pancreas into a human would be very very difficult - but it could be done.

The Third Stage of the Genetic Revolution is to grow an organ - inside the body. We would need to learn the secret of the bone, which continually re-grows itself on the run. We could then combine this knowledge with the knowledge of how to grow a human pancreas. You've probably seen people "morphing", or changing shape, in various movies. We could morph a diseased pancreas into a healthy pancreas inside the body - as the healthy one grew, the diseased one would fade away. Perhaps you could drink a virus that would trigger this to happen painlessly inside your body - maybe in 20 to 30 years or so.

The Fourth Stage of the Genetic Revolution involves improving parts or systems of the body, so that we could live "forever", say 1,000 years. After all, in the Bible, Noah is said to have lived for around 1,000 years. Practically all the systems of body slowly lose function with time - the skin, the bone, the lens in the eye which stiffens so that you gradually lose the ability to focus both near and far, the muscles, the kidneys, the heart and blood vessels, the liver, and so on. Once all of these have been re-juvenated, by "fooling around" with the DNA, we're looking at a healthy body that can tear around like a teenage body for 500 to 5,000 years. This could happen maybe 50 years from now.

Compared to the life spans that we have today, a few thousand years is pretty close to immortality - so some people living today could be the first generation to live "forever", or the last generation to die.

The Fifth Stage of the Genetic Revolution would be to modify human DNA, so that (for example) we could live on a planet like Mars with only a simple garment - not a spacesuit - to protect us. We would have to survive sub-zero temperatures (without freezing) and the incredibly thin atmosphere of carbon dioxide (with a pressure about 160 times less than our own). This level of skill with genetic engineering should be reached within three quarters of a century - roughly the same time it took to go from the first aeroplane to the first people on the Moon.

But before this can be useful, we make sure the whole world is at least at an average standard of living so that they can afford this, and other things. We wouldn't want 500 year old people living happily while others die at 40...