Is handing your DNA to the NHS really the best way to beat cancer?
The Chief Medical Officer says yes. But top cancer experts disagree — and others are gravely worried about privacy
Abrave new world of personalised cancer cures is almost upon us, it seems. This week, england’s Chief Medical Officer, Professor Dame Sally Davies, declared that all cancer patients should routinely have their entire DNA sequence scanned, so that individually targeted treatments can be found for them.
She wants patients’ gene profiles to be recorded so they can be used by doctors in a similar way to blood tests to learn more about patients’ conditions.
The process is called genome screening and can be performed at around £680 a time by high-tech machines that use chemicals to break up your DNA and then ‘read it’ gene by gene, much as your eye scans a sequence of letters to read a sentence.
Genes are the body’s basic instruction manuals, and they determine the way we look — from our eye colour to our physical shape — as well as myriad aspects of our health. Some may also provide faulty instructions to cells that lead them to turn cancerous.
Dame Sally hopes these £680 assessments will reveal which of a patient’s 20,000 individual genes is awry, and causes cancerous cells to thrive.
Tailor-made drug therapies — specific to the genes involved — could then be used, giving the best chance of a cure with the least pain and damage to our bodies. For any cancer patient, it sounds like a blessed miracle.
but sceptical voices in the medical community warn not only that this new frontier of science could be more hype than hope, but also that it could seriously compromise patients’ privacy.
In our modern era, when large-scale computer data thefts are commonplace, entrusting this crucial information to the leaky hands of the NHS could expose our precious genetic details to hackers, fraudsters and the likes of avaricious insurance companies which could use the information for commercial gain.
already, more than 31,000 NHS patients, including some with cancer, have had their entire genetic codes sequenced at 25 regional laboratories that have piloted the system since 2012 in a £300 million project.
Dame Sally says this information could improve patient care in about two-thirds of cancer cases, and that people with other conditions such as rare genetic diseases are also likely to benefit.
She declared: ‘I want the NHS across the whole breadth to be offering genomic medicine to patients where they can possibly benefit.’ It sounds so simple.
but leading british cancer expert Professor Tim Maughan warns that the promise of this technology is already so overblown it ‘ has become disconnected from reality’. as clinical director of Cancer research UK and the Medical research Council Oxford Institute for radiation Oncology, he recognises that personalised medicine is ‘widely considered as the way of the future for medicine’.
Yet he says progress in the battle against cancer has fallen below expectations in the vast majority of cases where gene testing has been used. Not least because cancer cells evolve and mutate so rapidly they can evade pinpoint attack from medicines that target them using gene technology.
Moreover, he explains, genes do not act alone, but change as they interact with their environment.
This ‘environment’ could be anything from the patient’s hormones to their diets, or even their mother’s stress levels when they were born. all these factors change the way genes work.
‘ Most common diseases are caused by a complex interplay of multiple genetic and environmental factors, making personalised medicine far more challenging,’ he warned this year in a journal called The New bioethics.
This not only means that genebased treatments can raise patients’ hopes falsely, Prof Maughan says, but they can also deplete resources from other medical fields where more effective cures may be found. ‘The current optimism for personalised medicine is distorting clinical consultations, resource allocation and research funding,’ he complains.
Other experts agree. German scientists warned in the journal Public Health Genomics that we need far more than just a patient’s DNA map to create personalised cures.
They say scientists would need to decode numerous other massively complex factors, such as the way the cancer cells mutate and how the patient’s immune system reacts, to consistently provide effective cures. but this would mean analysing so much data that no one could make sense of it.
Nevertheless, Dame Sally Davies is persisting with her aim to introduce widespread genome testing.
She is also trying to convince us that our most personal data is safe in NHS hands. Indeed, her report stresses that patients can be assured their genetic data will be stored securely and ‘de-identified’ so their privacy is protected.
Yet we all know government-held data can all too readily fall into the wrong hands. Just this week, the royal Free NHS Foundation Trust was censured for unlawfully handing 1.6 million confidential patient records to Google.
The official privacy regulator, the Information Commissioner’s Office, said the trust failed to tell patients it was giving their medical records to the internet giant as a part of a trial to diagnose acute kidney disease.
‘ Patients would not have reasonably expected their information to have been used in this way,’ said elizabeth Denham, the information commissioner.
Critics warn that although the proposed NHS database of people’s genes will be anonymised, safeguards can easily be cracked, allowing our most personal information to be hijacked and misused by commercial companies and scammers for financial gain.
If insurance companies, banks or pension providers got hold of our genetic data for example, millions of us could be barred from getting health insurance, credit and pensions on the basis that our DNA revealed potential diseases that would make us ‘too high risk’.
Dr Ian Cox, a former GP and now consultant chief medical officer at the insurance company Gen re, told a recent seminar at medical science charity the Wellcome Trust that people considering a DNA test for their health should first take out all the insurance policies they need, lest the results send their premiums spiralling.
Hardly a vote of confidence in the system to keep your most private details safe.
Under Dame Sally’s proposed genome scheme, your anonymised data would be shared between the NHS and commercial health-science companies, for research purposes.
Genomics england, the organisation which piloted the system says: ‘ There is a very small risk that participants could be identified by someone,’ although it insists this would be difficult.
Yet three years ago, a study in the respected journal Science managed to identify five out of ten people it investigated from their supposedly anonymised genomes, which came supplied with basic biographical information such as the patient’s age, sex and the area where they lived.
Melissa Gymrek, a U.S. health information researcher, simply used publicly available genealogies from the internet, and a computer program that pulled together scraps of information from online sources, to build profiles of the individuals who’d taken the test.
because commercial laboratories can study the data derived from the new scheme, critics fear the information could be used to the disadvantage of millions of patients. The worry is that such data could be leaked by someone acting illegally.
Indeed, Dr Helen Wallace, who runs the UK pressure group Genewatch, warns that Dame Sally’s proposal raises multiple concerns about the security of patient data.
‘The Government has promised us a new data protection law in the autumn, but we don’t know the details, or if it will be as strong as european law,’ she says.
‘We are very concerned that the new legislation will contain loopholes and exemptions that allow patients’ DNA data to be given away by the NHS without their knowledge.’
Dr Wallace is also concerned that criminals may use misappropriated DNA data to blackmail people — if they found a genetic flaw that rendered someone unfit for their job, for instance — or to try to sell expensive but useless therapies.
‘even now, patient data can sell for more than financial information on the dark web,’ she says, referring to the secretive area of the internet often exploited by criminals. ‘So the scammers must see a lucrative use for it.’
all these potential threats might seem a worthwhile price to pay if our cancers are to be cured.
but with leading scientists questioning whether personalised treatment actually works, we could simply be exposing ourselves to extreme risk for little or no benefit at all.