Hello humans. My name is Nick Dent and this...
is your Genome Project.
Now when this was completed it made a lot of people very excited.
The UK science minister Lord Sainsbury said,
'We now have the possibility to achieve all we ever hoped for from medicine'.
President Bill Clinton said,
'We are learning the language in which God created life'.
And my mother said, ‘What a lot of big white books!’
So what is it that got my mother and William Jefferson Clinton so excited?
Well, the Human Genome Project is a collaboration between several countries:
it was France, Germany, China, Japan, USA and United Kingdom
working together to map all of the genes – collectively known as the genome –
of the often less than humble homo sapiens.
So to put it marginally simpler,
this will tell you where to find all of the genes in human DNA.
These are the instruction booklets that your body follows when building a human being.
So how does your body use these to make a human being?
Well, these letters represent nucelobases in DNA.
Now here I have a model of DNA.
This structure was discovered in 1953 by James Watson and Francis Crick,
with honourable mentions to Maurice Wilkins and Rosalind Franklin.
So here we have the phosphate backbone,
but in the middle we have the nucleobases.
There are four different nucleobases:
there is Adenine which is represented in these books by an 'A';
Thymine, 'T'; Cytosine, 'C', and Guanine, 'G'.
So they bond here in the middle, forming the double-helix shape.
Now Adenine will only bond to Thymine,
and Guanine will only bond to Cytosine.
So if you know the structure of one strand,
you can actually use this to deduce the structure of the other one.
So how does a language using only four letters ordered by random chance
create the wonderful poetry that is my body?
Well, you've heard the story that if you give a monkey infinite time and a typewriter
he'd write the complete works of Shakespeare.
Well, if you only give him four letters he couldn't even type, 'Shakespeare'.
So the truth is this language doesn’t just use four letters;
these four letters are grouped into threes called 'codons'.
Theoretically, you could combine these letters in 64 different ways.
And these codons can code for 20 different amino acids.
Now if you think we have 26 different letters in the English alphabet
and these can make all of the wonderful words and stories that you've ever heard.
So 20 is starting to sound like a more viable number to create a human being.
So these amino acids combine to form proteins.
And these proteins can join together in bundles to form tissues.
This is why mutations can be so dangerous,
because if you change one codon it changes the amino acid,
which changes the protein, which changes how it combines.
And this can kill you
– or give you superpowers!
So as you can see by these books, you have a lot of DNA.
There are three billion letters or bases in these books.
And bear in mind, you have this information in nearly every single one of your cells.
And they produce a staggering amount of DNA.
If you stretched out the DNA from one cell it would reach two metres high,
that's roughly the height of these books.
And bear in mind, you have nearly 40 trillion cells in your body.
So combined they create enough DNA to stretch nearly 50 times around the world.
However, only 2% of our genome are actually genes.
This amounts to just under 21,000 genes.
This is less than a water flea; this is half as many as a potato.
Now most people you meet will be slightly more complicated than a potato,
so scientists soon had to realise that bigger is not necessarily better.
Changes in this 2% can affect many things:
it can affect your hair colour, it can affect your height,
and sadly it can even affect whether you live through childhood.
So there's a lot of amazing information hidden away in these books.
So you can imagine the excitement when in 2006 they finally finished this project.
They opened up the books; they looked at them and thought,
'Oh…'
Because essentially they had just created a dictionary for a language nobody could speak.
So for the last ten years they've been trying to decode these books.
So how do you find out what a gene does?
Well there are several different ways.
One way is to look at an animal that might have the same gene as us.
So when you think of experimenting on animals most people imagine lab mice,
however a vast amount of work is done on things like drosophila or fruit flies.
So, for instance, if you find a gene in them and you remove it,
and when they are born they don't have any eyes
you could deduce that perhaps this gene was to do with eye production.
However, it is rarely that simple.
A second way is to insert a gene into bacteria.
For instance, if you found a gene that was being expressed loads and loads in the pancreas
and you put it into bacteria and they started producing insulin,
you could deduce that perhaps this was the gene for insulin.
Finally, you can compare groups of humans.
So I actually have a genetic condition, one called psoriasis.
It's not the worst one in the world and I don’t have it particularly badly.
But if we got a group of people with psoriasis
and compared their DNA to a group without psoriasis,
any consistent differences could perhaps be a gene, which controlled skin production.
Now this can be done for any genetic disease, or indeed any genetic trait,
However, many traits are actually governed by many genes working together, such as height,
so it is not always that easy to pinpoint them.
So what if we actually find a gene which causes a genetic disease?
Well, many people think we should do nothing
because messing with this code is tantamount to playing God.
However, many people see this as the potential to remove inherited diseases from the human race
and improve the life of millions of people.
Scientists have been working on ways to alter the genome using ‘molecular scissors’
and over time these results have become more accurate and more reliable.
This gives us the potential to cure diseases as wide-ranging as cystic fibrosis to haemophilia.
Some people even believe that we could alter our immune system to combat diseases such as HIV.
So the future is coming
and the information in these books has the potential to change the world,
and I for one am quite excited.