How unlocking the genome has kick started a new medical era

Personalised medicine is all about you, who you are, what you have experienced and what you are made up of. In the year 2000, after 10 years of hard work, a working draft of the human genome was announced. This draft consisted of the identification and mapping of around 20,000 -25,000 genes. The identification and “decoding” of the human genome opened the door to a new breed of medical practise; personalised medicine.

So for a bit of the basics, our body is made up of trillions of cells, these cells are the “building blocks” of our body. They are the bricks from which your house is made up of. Each of these cells contains DNA. DNA is the “blueprint” for life or the instruction manual for cells – “the human for dummies” or something like that. Each cell contains nearly exactly the same DNA sequence, which is funny because in our bodies we have so many different cell types: Skin, brain, nerve, goblet and blood cells; the list goes on and on. A single cell has the potential to become any cell; they just need the right conditions. These conditions could be signals from other cells or hormones.

So anyway back to personalised medicine, certain genes or genetic mutations can cause an individual to be more or less susceptible to developing a disease (such as diabetes or breast cancer). Therefore if we can identify these slight genetic subtleties, we can predict the likelihood of an individual acquiring a certain condition/disease. So, once predicted, we can take steps to prevent this disease before it even occurs; such as maintaining a low cholesterol diet for someone who is genetically more prone to heart disease.

Personalised medicine also can affect our use of drugs. Each one of us responds to drugs differently, sometimes a drug will cure one person, while in others it will have no effect. This is because it might be metabolised too quickly. On the other hand a drug could be metabolised to slowly and as a result cause severe side effects. Currently we prescribe drugs on an educated trail and error basis. However with the advent of personalised medicine we can look at someone’s genetic code, genome and genes to predict how they will respond to certain drugs and prescribe accordingly.

The ability to predict disease susceptibility, course and treatment would be an extremely powerful tool for the practising physician. So understandable personalised medicine has become a very hot research topic. However there are many issues surrounding this emerging field of medicine.  First the technology, the first human genome sequence cost $30 billion and took ten years. This, as you can see, is too costly and too slow for everyday medicine. The good thing is things have sped up a bit and it is getting cheaper. It is predicted that soon we will be able to sequence a full genome for $1000, which is comparable to other medical tests on the market.

However once we get this mountain of data can we even use it? The answer is a bit. We have identified 1500 medically predicative genes, which is good but only the tip of the iceberg. Countless genetic variations are still very much hidden. So we have a major problem interpreting the data, it takes a long time and requires considerable expertise. Some companies are pioneering software to scan genomes and algorithms to predict medical risk resulting from your genes. However the feeling is that these are still far off from becoming medically useful.  You also very much get the feeling that personalised medicine is a rich mans game, are we really going to see advances in health care for poorer populations? I would have to say no. The costs are too high; therefore you have to question its actual impact on overall health.

Personalised medicine allows a tailor made therapy, which is both efficient and highly specific. It allows the right drug to go to the right person. It endows foresight into what potential illnesses are ahead of you. Personalised medicine has its problems but I think as technology advances it is a very real and exciting concept. I always think about the advent of computers. They used to fill a whole room, but now we have a computer with the same power in our mobile phones (well I don’t but all you IPhone users do!). The same will and is happening with personalised medicine; sequencing is getting cheaper and interpretation is improving. Soon people will be getting sequenced for fun and free sequencing will probably be given away when you open a bank account. The future for personalised medicine is exciting, however I do feel the medical impact will only be seen in developed world and only rich people will see the benefits. Lets just hope there is a trickle down effect and in the future we can all benefit from this rapidly emerging field.