Caroline Wright: 'An exciting time but there are going to be lots of questions about how accurate test will be'

Published on Monday 15 February 2010 21:33

THERE are many researchers and companies around the world who are looking for different methods of doing cheaper and faster DNA sequencing at the moment.

Most methods use a biological enzyme for their analysis, which can pose practical difficulties. So from that point of view, this new test using chemical analysis could be extremely useful.

Regardless of the technology used, all of these tests will have to prove that they have an acceptable level of accuracy before they can be used outside of a research setting.

If you are using a test to see if someone is susceptible to certain diseases, obviously you want to make sure that the results are correct.

When it comes to applications of this new type of technology, it is a hugely exciting time but there are going to be lots of questions about how accurate it is as well as how useful it will be.

No-one is yet sure whether these new DNA sequencing technologies will eventually be used to check the whole genome or will be targeted to certain conditions.

But before we start thinking about using a technology like this in the NHS, we have to see the results to show how accurate it is and how much it will cost, as well as considering what it will be used for and what safeguards need to be put in place.

At the moment, this type of technology is definitely not ready for the NHS.

However, there are already tests available for some conditions in the private sector and there is an ongoing debate about these services.

You can even buy a whole genome sequence – a complete analysis of your entire genetic make-up – as a consumer, though the $50,000 price-tag means that it is not something available to all.

There are also tests available to consumers which look at a small number of genetic variations and from that try to tell you about your susceptibility to various diseases.

Unsurprisingly, people disagree about whether offering this type of test without medical support is irresponsible, or if everyone has the right to access this information about themselves. On the scientific level, there is also debate about whether the information they give you is scientifically accurate and clinically useful.

There are a huge number of genetic variations which could contribute to disease in different ways and in varying amounts.

These range from those where if you have the gene you are almost certain to develop the disease, such as Huntington's and cystic fibrosis, to others where they indicate you may just have a slightly higher risk of illness.

For something like heart disease, genetics only plays a small role and you are much better off using traditional measures such as cholesterol, weight and smoking as indicators of your level of risk.

• Caroline Wright is head of science at the Foundation for Genomics and Population Health (PHG Foundation).