“In a country nervous about genetically modified crops, we are making the foolhardy move to genetically modified babies.” So said MP Jacob Rees-Mogg in a on draft regulations to allow trials of controversial techniques that might allow women with mitochondrial disease to have healthy babies.

If approved, the regulations would, for the first time, allow human germ-line modification – in which DNA is changed and the change remains inheritable.

The technique at the heart of the debate is mitochondrial transfer. Mitochondria are the energy generators of cells and have their own DNA, which is separate from DNA in the nucleus. Mitochondrial DNA is inherited via the maternal line, from mother to child. So to prevent a woman with faulty, disease-causing mitochondria from passing on her condition, a female donor supplies healthy mitochondria.

However, the phrase mitochondrial transfer does not fully describe what is involved: the manipulation of an entire human egg. In reality, the nucleus is removed from an egg or single-celled embryo from a woman who has mitochondrial disease and is then transferred into a donor egg or embryo that has healthy mitochondria. The resulting baby would have the DNA of three people – the mother and father’s nuclear DNA and the donor’s mitochondrial DNA.

The UK Department of Health’s latest on whether to permit human trials ended on 21 May. A free vote on whether to allow mitochondrial transfer is expected in parliament later this year. If agreed, the UK’s Human Fertilisation and Embryology Authority (HFEA) could allow doctors to offer the technique.

That a Catholic and Conservative politician such as Rees-Mogg voiced opposition to this might seem predictable, but MPs from other parties have supported his scepticism.

All those who spoke on the issue thought that allowing human trials would be premature. Key worries include remnants of mutant mitochondrial DNA that persist despite the treatment, and the disruption of complex interactions between mitochondrial genes and those in the cell nucleus. There are also daunting challenges in terms of designing meaningful trials, or safe ones, because pregnancy and childbirth pose major health risks for women with serious mitochondrial disorders.

Furthermore, MPs were troubled by a lack of proposals to legally require follow-up studies for a technique that may have implications not only for the children born as a result of it, but for their descendants.

Their doubts were fuelled by recent conducted by the US Food and Drug Administration (FDA). The FDA committee did not consider ethics or the law, just the science. It warned that the evidence does not yet support the use of mitochondrial transfer in people. In the US there are no plans to change the law to allow this technique in humans.

The FDA’s well-balanced briefing document previewed risks but noted that “the full spectrum… has yet to be identified”. It also addressed efficacy: because only one study has used eggs or embryos containing abnormal mitochondria, “it is not clear whether these data provide any support for the potential effectiveness… in humans”.

In his , Evan Snyder, head of the FDA body advising on the science, characterised the “sense of the committee” as concluding that there is “probably not enough data either in animals or in vitro to conclusively move on to human trials” without answering further questions. Concerns “revolv[ed] around the preclinical data with regard to fundamental translation [into people], but also with regard to the basic science”.

In addition, US National Institutes of Health note that the process will “require women to donate oocytes, a procedure that has health and ethical implications, including the health risk to the donor from… hormonal treatments needed to induce oocyte production”.

National stereotypes about the cautious British versus the go-getting Americans are reversed in this debate. The FDA position is in contrast to that of UK authorities, who want to proceed full steam ahead.

“It is only right that we look to introduce this life-saving treatment as soon as we can,” said the Chief Medical Officer for England, Sally Davies, in ahead of the release of draft regulations to permit the use of mitochondrial transfer.

On 7 March the HFEA opened a required on safety, but surprisingly it allowed only two weeks for submissions. The results, out on Wednesday, will be considered by the Department of Health as it finalises proposals to go before parliament later this year.

The department’s own says that the intended effects of the proposal to allow mitochondrial transfer are: “to enable safe and effective treatment for mitochondrial disease; to ensure that only those mothers with a significant risk of having children with severe mitochondrial disease would be eligible for treatment; [and] to signal the UK’s desire to be at the… cutting edge of medical techniques.”

If the evidence for safety is lacking, and if the handful of women intended as the beneficiaries could be put at risk by trialling the techniques, that only leaves one clear motive for hurriedly changing the law: positioning the UK at the frontier of scientific research on mitochondrial disease. But as any aficionado of spaghetti westerns knows, the frontier can be a lonely and dangerous place.

IT’S 2008. The is chronicling a celebrity “spit party”, at which notables – nicknamed the “Spitterati” – eject saliva into tubes to find out their risk of developing illnesses such as diabetes, heart disease and cancer. The firm involved is 23andMe, a direct-to-consumer genetic testing company whose service was named Invention of the Year by Time magazine.

Fast-forward five years. 23andMe receives a demand from the US Food and Drug Administration (FDA) to stop selling its health-related tests pending scientific analysis. In a separate event, a Californian woman, Lisa Casey, files a $5 million class action lawsuit alleging false and misleading advertising. 23andMe suspends sales of its test, putting paid to its target of reaching 1 million customers by the end of 2013. Where did it all go wrong?

In November, after what the FDA describes as years of “diligently working to help [23andMe] comply with regulatory requirements”, the agency sent a to the firm’s CEO Anne Wojcicki. It stated that 23andMe’s Personal Genome Service was marketed without approval and broke federal law, since six years after it began selling the kits, the firm still hasn’t proved that they work.

“Six years after it began selling the genetic-testing kits, 23andMe hasn’t proved they work”

Doubts go back a long way. In the year of the spit party, the American Society for Clinical Oncology that concluded the partial type of analysis involved wasn’t clinically proven to be effective in cancer care. In 2010 the US Government Accountability Office concluded that .

What 23andMe offered was a $99 test for 250 genetically linked conditions, based on a partial reading of single-nucleotide polymorphisms (SNPs). These are points where the genomes of different individuals vary by a single DNA base pair. There are some 3 billion base pairs in the human genome – this test targets only a fraction of them. Different companies sample different SNPs and so return different results for the same person.

To illustrate this point, in his book Experimental Man, science writer David Ewing Duncan recalled how he received three conflicting assessments of heart attack risk from three different companies. The director of one, – no longer offering such tests – telephoned him from Iceland to urge him to start taking cholesterol-lowering statins. Yet the other two tests – one from 23andMe, one from Navigenics, which no longer offers consumer tests – had rated him at medium or low risk. Given that some statins carry side effects such as muscle weakness, Duncan might have been ill-advised to follow deCODE’s urgent advice.

This is the root of the FDA’s concerns. In its letter to 23andMe, it raised the risk that customers could get false information that leads to drastic and misguided medical steps. Wojcicki now says: “We want to work with [the FDA], and we will work with them.” But is it too little, too late?

And what of the class action lawsuit, brought by Casey after buying a test? It focuses on the test’s accuracy but goes further, targeting what Casey’s attorney calls “a very thinly disguised way of getting people to pay [23andMe] to build a DNA database”.

By asking customers to fill in surveys about health and lifestyle, 23andMe has been creating a valuable “biobank” for patenting purposes and industry collaboration. The firm has always sought customer consent for use of identifiable data and hasn’t disguised its aim. “The long game here is not to make money selling kits, although the kits are essential to get the base level data,” says 23andMe board member Patrick Chung. “Once you have the data, [23andMe]… becomes the Google of personalised healthcare.”

Last June, this strategy culminated in a potentially lucrative genetic . The company had offered its test free to people with the illness and might have expected praise. But an angry customer wrote: “I had assumed that 23andMe was against patenting genes. If I’d known you might go that route with my data, I’m not sure I would have answered any surveys.”

What impact will all this have on 23andMe’s brand strategy? The firm has tried to create a sense of solidarity, emphasising what it called “common interests, affinities and passions”. As the firm wrote on its blog in 2008: “Wikipedia, YouTube and MySpace have changed the world by empowering individuals to share information. We believe this same phenomenon can revolutionize healthcare.”

If customer trust is threatened, that won’t happen – even if the firm switches to sequencing the whole genome or exome (the protein-coding parts of the genome), avoiding the worst inaccuracies of SNP testing. Whole-genome sequencing has become cheaper, although it’s still out of reach of the mass market the firm needs to build the biobank. Earlier this year the company piloted a whole-exome service for $999.

Given its status as the poster child of mass-market genetic testing, do 23andMe’s travails affect personalised medicine more generally? In the year that it started operations, 2007, then-Senator Barack Obama introduced his Genomics and Personalized Medicine bill, remarking that “in no area of research is the promise greater than in personalised medicine”. Many advocates expected the shift to start at the popular, consumer level.

So while the most consciously populist genetic testing service wrestles with its critics in the months ahead, there is a growing danger that wider public acceptance of personalised medicine in the clinical setting may also suffer in the fallout from 23andMe’s woes.

This article appeared in print under the headline “Testing times”

ADVOCATES of personalised medicine claim that healthcare isn’t individualised enough.

Backed up by the glamour of new biotechnologies such as direct-to-consumer genetic testing, personalised medicine – what I call “Me Medicine” – appears to its advocates as the inevitable and desirable way to go. Barack Obama, when still a US senator, declared that “in no area of research is the promise greater than in personalised medicine”.

This trend towards Me Medicine is led by the US, but it is growing across the developed world.

In contrast, “We Medicine” – public-health programmes such as flu shots or childhood vaccination – is increasingly distrusted and vulnerable to austerity cuts. Yet historically this approach has produced the biggest increase in lifespan. Even today, countries with more social provision of healthcare and less individualistic attitudes have better health outcomes across all social classes.

Contrary to the claims of its proponents, the personalised approach hasn’t yet delivered a paradigm shift in medicine. A 2012 Harris poll of 2760 US patients and physicians found that doctors had recommended personal genetic tests for only 4 per cent of patients. The Center for Health Reform & Modernization, run by US healthcare company UnitedHealth, put the figure at just 2 per cent.

“Contrary to the claims of its proponents, personalised medicine hasn’t yet delivered a paradigm shift”

But money is still pouring into Me Medicine. In July, the UK government announced that it would offer private companies a subsidy from a £300 million fund to encourage investment in its personalised medicine initiative, Genomics England. Last year the US administration increased the National Institutes of Health budget for personalised medicine, while cutting the budget for the Centers for Disease Control and Prevention’s Office of Public Health Genomics by 90 per cent.

Of course it would be nice if we could afford both, but in reality there’s a growing risk that “me” will edge out “we”. If it does, it won’t be because the science is better or the outcomes more beneficial. In some instances of Me Medicine, clinical outcomes are worse than the We equivalent. For example, according to the UK’s Royal College of Obstetricians and Gynaecologists, private umbilical cord blood banks, which ostensibly provide a personal “spare parts kit” for the baby, produce poorer outcomes than public cord blood banking.

It is true that in some areas of Me Medicine, such as genetically individualised drug regimes for cancer care (technically known as pharmacogenetics), there has been genuine progress. For example, vemurafenib, a drug for aggressive melanoma, was reported in a 2012 New England Journal of Medicine article to extend the lifespan of 1 in 4 patients by seven months if they carry a specific genetic mutation in their cancer.

But only about half of those with the “right” type of tumour responded, and the mutation in question only occurs in about half of such melanomas. What is more, pharmaceutical firms will probably charge more for such drugs than for mass-market ones. They will be expensive, may benefit only a subset of the population and could leave cash-strapped state healthcare systems facing difficult decisions about where to allocate resources.

A month after the melanoma study, much less encouraging results for pharmacogenetics were reported in another NEJM article. A genome-wide analysis of biopsies on four people with kidney cancer showed that separate samples from the same tumour can have different mutations, so a drug that targets one may leave other parts of the tumour untreated.

Given that the scientific evidence alone doesn’t explain all the interest in personalised medicine, what does? Many retail genetics companies have “me” in their name – notably 23andMe, DeCODEme and Knome – so does it boil down to narcissism? I doubt it. There’s nothing narcissistic about pharmacogenetics.

Another possible explanation is the favourable connotations of “personal” and “choice”. “We” measures such as childhood vaccination are routinely attacked as an invasion of parental choice, while accounts by people who have paid to have genetic profiles drawn up often include themes of individual self-discovery.

A third explanation is commercial: that in personalised medicine, pharmaceutical companies see a way to rescue themselves from the demise of profitable patents on mass-market drugs, so they promote the shift from We to Me.

As Mark Levin, former CEO of Millennium Pharmaceuticals, put it in 2012: “Business incentives must be put in place to encourage private investment and further develop the pipeline of new personalised medicine products.”

The landscape has clearly changed. Twenty years ago, who could have predicted that people would pay to have a spit sample genetically tested or to bank their child’s umbilical cord blood?

As well as unpicking and unpacking the science, we need to consider the social and economic context behind Me Medicine. How can we balance the role of the individual and the communal in healthcare? And how did we move from the original vision of genetic biomedicine as a communitarian endeavour – the Human Genome Project was ostensibly for the benefit of all humankind – to the personalised medicine paradigm?

These are big questions that need to be asked. If we do embrace personalised medicine, it should only be after a thorough review of the evidence and careful analysis of the social landscape in which we’re making that choice.