Understanding the impact of genomic data

Updated on 12 February 2015

The genomic era is upon us. From the Government’s pledge to sequence 100,000 genomes to the launch of 23andMe, a private company that can offer personal genotyping for £125, having bits of your genome sequenced has become a very accessible option. Millions of us will be able to receive information encoded in the three billion chemical bases that offer instructions for everything we are and everything we will be. The big question now is, what do we want to know?

Genetic testing, where we look at a small section of DNA known to be linked to a specific condition, is already widely used by the NHS for diagnosis of illness with a genetic basis. This can be an emotional moment in a patient’s life for many reasons. With genetic conditions, there is a family context to consider; patients may have lived-experience of seeing a family member suffer through the same condition and often patients are worried about passing on conditions to their children.

In clinical genetics, results of genetic tests are communicated by clinical geneticists and genetic counsellors and both are available to talk to a patient through the implications of the findings and provide information to be shared with their family members.

Currently there are just under 300 genetic counsellors working in the UK, where thousands of genetic tests are being carried out in clinics each year. The number of tests will only increase as we understand more of what our DNA has to tell us about disease and as the cost of sequencing continues to fall. There’s a clear need to increase the number of genetic counsellors and to train a workforce of doctors and nurses who will increasingly encounter genetic data.

Genetic counsellors talk patients through implications of findings and advise them on how to share findings with family. Credit: Anthea Sieveking , Wellcome Images

There’s another crucial shift that’s needed: a move from genetic counselling to genomic counselling. The difference is one of scale. The amount of information contained in our genome is potentially enormous and the number of exome and genome sequences being done outside clinical genetics is on the increase. The resource of data (the exome/genome) can be mined in an almost infinite manner of ways to yield useful clinical answers - the question is....what is it actually helpful to know and share? The other issue relates to accessing the technology - virtually every area of medicine now is able to integrate genomics into patient management - oncology, paediatrics, obstetrics, dermatology and so conversations involving genomic data will be happening across a whole health service – other questions are.....how to communicate genomics effectively? How can mainstream medical services care for a whole family (usually the domain of clinical genetics services)?

Existing genetic counselling models used in clinical genetics will be a strong starting point for thinking through how to translate genomics into mainstream medicine. But capacity and training will be an issue. Explaining genomic results requires knowledge of bioinformatics, sequencing, data interpretation and visualisation as well as ethical, legal and social issues. It may be that genomic counselling becomes a distinct profession, or that genetic counsellors take a central role in training health practitioners in the technical and empathic skills required.

How this need will be filled remains to be seen but what is certain is that health services and genetic counsellors need to begin this discussion now to prepare for a future that is very close at hand.