The future of personalised medicine lies in your genome by Stefano Gortana

EDITED: 28/07/2016 | PUBLISHED: 27/07/2016

Let’s set aside the complex science of genome sequencing, genetic mutations and comparing genomic datasets for a moment to acknowledge the important overarching fact: we all want better healthcare. This includes not only the early prediction and prevention of disease, but also earlier, more accurate diagnosis followed by a treatment regime tailored specifically to a particular patient, all available at an affordable price. Any developments in science or technology that contribute to the pursuit of these ambitious goals should not only be welcomed, but pursued with rigour. With this undeniable truth established, genomic medicine cannot be ignored.

Why care about genomics?

Genomics England explains that one complete set of all your genes, including the DNA between them, is called your genome. Interestingly, genes (sequences of DNA that code for proteins) account for less than 5% of your genome (there are only about 20,000 genes in a genome), but the combination of genes and the DNA between them comprise the 3 billion DNA ‘letters’ contained within a genome. Hidden within this simple code lies crucial information necessary to provide more personalised care.

By sequencing and analysing genomes, and combining the data with other medical details and records, comparisons of many thousands of patients can be made and robust conclusions drawn. This data could reveal underlying genetic conditions that have caused clinical symptoms and whether they were inherited or not. It may also give clues to potential features of disease, any therapies that might be available and how patients may respond to them. Even for a single cancer patient, sequencing and comparing DNA from healthy tissue and tumour tissue may reveal key genetic changes that have driven the disease and direct which treatments might be most effective. 

The 100,000 Genomes Project – heading in the right direction

The pursuit of such groundbreaking discoveries lies at the heart of the 100,000 Genomes Project. Launched in 2012, Genomics England was created and tasked with sequencing 100,000 whole genomes over five years. Given the short timeframe, the focus has been placed on collecting samples from people where the health benefits of genomic information are currently the greatest. More specifically, these include samples from patients with rare inherited diseases and cancer, plus their families, and those from infectious disease agents. However, the intention has always been to lay the foundations for a new genomic medicine service across the NHS.

Considerable progress has been made since 2012. Project infrastructure has grown to include thirteen NHS Genomic Medicine Centres (GMCs), a central sequencing facility and data centre near Cambridge, and a host of partnerships (public sector, charitable and commercial, national and international) and other initiatives designed to drive the project and capitalise on the extensive data it produced. Working on over 200 diseases, Genomics England has already sequenced over 11,000 genomes (including 3,000 from the bacteria that cause tuberculosis) and has begun to deliver genomic diagnoses to some participants with rare diseases.

Barriers to an efficient NHS genomic medicine service persist

Clearly, the efficient sharing of patient data within the NHS is of the utmost importance if the UK is to build on the foundations of the 100,000 Genomes Project and get the maximum benefit from genomic medicine. It is only by comparing genomic and medical data from very large numbers of patients that we can better understand the causes of disease, how diseases develop, what treatments work best and what new treatments can be pursued. Unfortunately, work by the PHG Foundation reveals that barriers to efficient data sharing exist within the NHS. Data has not been comprehensively stored in one location and it is not even routinely shared between existing clinical genetics laboratories, partly due to concerns about legal requirements for safeguarding data and the degree of transparency, security and anonymity required. Following on from the National Data Guardian’s recent review of Data Security, Consent and Opt-Outs, it is clear that work specifically examining routine clinical genomic data sharing in the NHS is needed.

Even if the data were shared efficiently, an additional challenge involves the clinicians themselves. There are currently over 130,000 specialists and GPs working in the UK, all of whom need to understand how to incorporate genomic medicine into their routine work in providing first-rate patient care. This includes understanding when it may be appropriate to refer a patient for a genetic test and how results could direct their management. 

Public understanding of the importance of data sharing also remains low, although the 100,000 Genomes Project feature in the current ‘Our Lives in Data’ exhibition at the Science Museum and a new Wellcome Trust project ‘Public confidence in the use of patient data’are encouraging first steps towards addressing this problem.

As Jo Churchill MP reiterated this month, genomic medicine has the potential to radically improve healthcare in the UK, but the real challenge lies in bringing this technology and understanding to mainstream hospitals, for all patients who can benefit. There are wider NHS issues that need to be addressed for the genomic medicine revolution to succeed and while the success of the 100,000 Genomes Project cannot be guaranteed, Jo is correct in concluding that it is an important challenge as well as an opportunity that must be seized.