The buzz phrase among a small army of biotech companies looking to get a foothold in the ever-expanding health market is “personalised medicine” or, as it’s also known, “precision medicine”. At the core of this concept is the understanding that we are all different, with different biological make-ups and different environments. Therefore a one-size-fits-all approach to diagnostics and treatment is long out of date.
One of our most important areas of difference, and certainly the one that is increasingly subject to scientific scientific analysis, is our personal genome. The 21st-century revolution in genetics has been as dramatic as that seen in computer technology. The first human genome to be sequenced took 13 years. It can now be done in a day. The genetic information that cost about £2bn to extract in 1990 can now be got for a couple of hundred pounds.
All of which has led to a huge expansion in genetic research, as well as the arrival of private firms offering direct-to-consumer genetic profiles. But what does it amount to? Are we on the verge of a new era of bespoke medicine, in which each of us is treated as biologically unique with our particular genetic profile determining precisely what care we receive? Or does all the hype conceal a far more limited vista? And what ethical concerns involved in sharing our most essential information, our very own genetic code?
“There are conditions, particularly rare diseases such as childhood developmental disorders, where genome sequencing is extremely beneficial, and may even be life-saving for some individuals,” says Caroline Wright, senior lecturer in genomics at the University of Exeter. “There are also conditions – many common diseases, for example – where there is currently no evidence that genome sequencing is beneficial to individuals.”
Earlier this year, the health secretary, Matt Hancock, got into hot water when he announced plans for predictive tests for common cancers and heart disease to be introduced by the NHS without delay. He said: “Every genome sequence moves us a step closer to unlocking life-saving treatments.”
He cited his own experience of having his genome sequenced. He found he had a higher than average predisposition to prostate cancer, so he went to his doctor for a test.
But critics argued that Hancock had misinterpreted his risk and unnecessarily burdened the NHS with his concerns.
“Screening healthy people using any type of technology is likely to falsely identify individuals as having – or being at risk of developing – diseases they don’t have and won’t get, causing them psychological and often physical harm, and costing the NHS quite a bit in unnecessary testing and potentially treatment,” says Wright. “A national health service should be primarily for proven tests and treatments, which includes genome sequencing in certain cases.”
But even critics of Hancock’s plan, such as Anneke Lucassen, professor of clinical genetics at the University of Southampton, do see the need for greater sequencing, in particular from a more diverse range of people.
“We don’t have nearly enough evidence yet of what genomic variants do in different contexts, and we need much more research before we can realistically use much of this in healthcare,” says Lucassen. “As we have very little data about anything other than northern European ancestral genetic variation, we urgently need to find out more about other ancestries.”
Much of the available genome data at presently available comes from the government-backed 100,000 Genomes Project, which has sequenced genomes from NHS patients affected by rare diseases or cancer, making the results available to approved researchers. More controversially, private companies have taken advantage of the cheapness of sequencing, offering simple kits direct to consumers.
A recent arrival is Sano, a startup in Cambridge Science Park. Unlike some more established names, such as 23andme, which offer general sequencing reports, Sano seeks to act as a matchmaker between people with particular conditions (or a genetic predisposition to them) and researchers in related fields.
Its chief executive, Patrick Short, 28, is from North Carolina. He did his doctorate in mathematical genomics and medicine at Cambridge University and set up Sano three years ago with two fellow PhD students. He says there are three main phases in the advancement of personalised medicine. First, improved diagnosis, then improved treatment as a result of better diagnosis. And the third stage, he says, will be much earlier detection and prevention.
“This is one of the great promises of genetic medicine,” Short says. “Because our DNA does not change through our lives, our DNA – along with information about our environment and behaviour – should be a powerful tool for moving towards proactive rather than reactive healthcare.”
But, because our DNA is key to who we are, thatandwith our genome our private code, there is a lot of sensitivity about the protection of genetic information. Developments in the field have given rise to several ethical issues. In terms of identification, in America there have been cases of DNA samples being traced, via close matches on genomics websites, to relations of a suspect in a crime, and this has led to arrests. It’s just one of the more dramatic ways that our genetic data, once in the public realm, can affect not just ourselves but others.
Looking to the future, there are concerns that health insurers and employers may demand or get access to personal genetic data. Even today there are fears that DNA information is being traded without the knowledge or informed consent of the consumer (as often consent is buried deep within long-winded agreement forms).
However, Jeffrey Skopek, a lecturer in medical law and ethics at the University of Cambridge, questions the belief that all things genetic require greater protection than other information – a belief he terms “genetic exceptionalism”.
“There’s lots of information about ourselves that is health-related, from which health inferences can be drawn, which we expose to the world and our employers all the time,” he argues. “It could be the case, for example, that algorithms looking at your Facebook likes will be able to predict health outcomes.”
Sano, which offers personalised reports based on genome sequencing, prides itself on leaving consumers in charge of their data, so nothing is passed on for research purposes, even anonymously, without signed agreement. Short says: “We built our platform specifically to allow participants to have full control over data use.”
The default setting on Sano’s website is to ask for consent each time the consumer supplies new information, to avoid the danger of anyone accidentally making their data open-access.
Short believes consumers have been misled by many genetic testing companies, which, he says, “often sacrifice scientific integrity to sell kits”. There have been cases of false positives, where consumers were led to believe they were predisposed to a condition, and false negatives where the consumer was wrongly given an all clear. Such mistakes have occurred partly because most sequencing tests analyse a tiny fraction of DNA, and thus may pick up some mutations without noticing others. Also interpretation of genetic information is complex and requires a sophisticated understanding of a person’s genome and environment.
In the US, 23andMe had its Food and Drug Administration (FDA) approval withdrawn for a couple of years, following concern about inaccurate results. It was reinstated after the company took steps to meet FDA regulations. Now the firm focuses on a selection of conditions for which there are known genetic markers, such as type 2 diabetes, breast cancer and coeliac disease, and emphasises that these markers only influence your chances of developing a condition.
In July, Dante Labs launched a consumer genetic testing service. A “super premium, whole genome” sequencing test on samples sent to its lab in L’Aquila, near Rome, currently costs €599 (£500). For this sum users receive a “full check-up for all common and rare diseases”.
Sano, Dante, 23andMe and other testing companies allow users to download their raw data. They can upload this to a third party site such as Genomapp for further interpretation. In the case of Genomapp you will be informed via its app about your risk of developing some 300 conditions and diseases.
So while the testing companies may try to ensure they deliver information to their customers in a responsible way, there is nothing to stop users shopping their data around for further analysis. As Skopek notes: “There’s a certain set of concerns that arise when the physician is out of the equation.”
Sano aims to provide a next-generation sequencing service, with genetic counsellors available, a doctor involved and good links to the NHS. But that is only an aim, and not a plan Short expects to see realised for at least a year. Given the time it takes to form working relationships, even a year may be highly optimistic.
In the meantime, says Short, Sano is offering three types of testing kit. Its Genotyping kit, costing £125, analyses less than 0.02% of a person’s DNA. Exome Plus measures up to 2% of your DNA and costs £450. For £950 you can get all your DNA measured with the Whole Genome option.
“The majority of our research projects are connecting people who already have a condition diagnosed,” says Short. So people with psoriatic arthritis can, as Short puts it, “contribute to research and learn more about how genetics might affect severity”. There’s a similar study up and running for people with stomach ulcers.
But what of people without a known condition? If none of the kits provide diagnosis at the moment, what is it that they do offer?
Well, you can learn about how such traits as odour detection, circadian rhythms, coffee consumption, nicotine dependence and male pattern baldness are influenced by your genes. It’s intriguing stuff but not perhaps the kind of analysis that will encourage many people to tick the £950 box.
The main body of Sano’s work is matchmaking, putting together those with rare diseases and the researchers looking into them.
One project the company is involved with is working with a patient support group for those with Phelan McDermid syndrome, a neurodevelopment disorder caused by a mutation of the Shank3 gene. Children born with the disorder suffer from poor head control and low muscle tone, and typically exhibit developmental and speech delays. The company has analysed the DNA of a number of families with the disorder in what Short described as a “grassroots, patient-led” initiative.
These are promising signs, pointing to a new, patient-empowered future. But in terms of personalised or precision medicine, it’s all rather vague and hopeful. That, however, is where the science of genome sequencing mostly is right now – vague and hopeful. It promises a great deal and, in time, will probably deliver on many of those promises. As Wright says: “For some people genome sequencing is very predictive and hugely useful. For most people, at this point in time, it is neither.”
But the greater the number of genomes sequenced, the more that balance will shift. And when that happens, genetic medicine is going to become much more precise and, ultimately, far more personalised.
