Everything about Genetic Health's opulent Harley Street clinic says "money". As I sit nervously thumbing through copies of Harrods magazine in a comfortable armchair, smartly dressed secretaries in high-heels glide past, over the varnished wood floors.
I'm waiting for a consultation with Dr Paul Jenkins, who will talk me through what the company calls its "Premium Male" service - an analysis of my genetic makeup. Some weeks ago I sent Genetic Health a handful of swabs that, as per the company's instructions, I had rubbed around the inside of my mouth. This inelegant procedure picks up the cells needed for the DNA analysis.
At a cost of £825 Genetic Health creates a personalised readout of 42 genes which, according to the website, will allow me to "take control of your life and your health". This is a long way from a full genome sequence, but the company says it looks for crucial genetic changes that have been linked to disease.
"Based on your individual genetic profile," reads its blurb, "one of our medical experts will guide you on which lifestyle changes to make as well as which supplementation to take that will improve the quality of your life, extend the active period of your life, and most possibly enable you to live longer."
The genetic testing industry in the UK is still small. Brian Whitley, Genetic Health's director, estimates that between 2,000 and 5,000 people here have used a gene-testing company, but this is set to grow rapidly as the costs come down. 23andme, a US company which is part owned by Google, has dropped the price of its services to $399 (£270), and held a "spit party" during September's New York fashion week at which guests including Rupert Murdoch, Ivanka Trump and Chevy Chase were invited to gob into a plastic cup to find out more about their genes.
The pitch from the companies is that knowledge is power. If you discover that your genes make you more prone to obesity say, then you might put more effort into eating better and going to the gym. But critics say that regular exercise and a good diet yield important health benefits whatever your genetic makeup, so knowing your DNA changes nothing. Worse, it might offer false reassurance that you will not develop one disease while worrying you unduly that you are at high risk of another.
I'm still not sure whether I want to peer at my genetic horoscope. If I decide to sit in front of the TV chain-smoking Marlboros and stuffing my face with cream cakes washed down with tequila shots I have no one to blame for the consequences but myself. But my genes are different. There is nothing I can do to re-shuffle my genetic deck and if I don't like Genetic Health's analysis I can't go back and un-know the information. My grandmother died a long, drawn-out and distressing death from Alzheimer's disease. Do I really want to find out, for example, that I'm at high risk of that disease when there is no immediate prospect of a cure?
And the decision to take the test does not just affect me. My six-month-old daughter shares half of my genes, so the answers will say a lot about her genetic future too, whether she wants to know about it or not.
Your genes can reveal some sobering information about you. A small number of rare mutations cause serious conditions such as Huntingdon's disease and cystic fibrosis with 100% certainty. Others, such as BRCA1 and BRCA2, lead to a three-to seven-times increased risk of breast cancer in women and a raised likelihood of other cancers. Geneticists are now also going after DNA changes that confer a more subtle risk. This requires massive long-term studies with thousands of volunteers. But the science is in its infancy and the results are difficult to interpret because the effect of any one gene is typically insignificant and depends on other genes as well as your lifestyle.
"The state of the scientific art is probably a long way short of where we want it to be in terms of predictions," says Professor Mark McCarthy at Oxford University's Centre for Diabetes, Endocrinology and Metabolism.
One way to think about it is to imagine your genome as a poker hand. Predicting whether you will develop high blood pressure by testing a handful of genetic variants is like trying to guess whether you will win the hand by looking at just one card.
A hand with an ace of hearts is statistically more likely to win than a hand with a five of diamonds, but it depends on your other cards. And of course your genome is much more complicated. There are around 25,000 genes that interact in complex ways.
This type of gene testing, says Andrew Hattersley, professor of molecular medicine at the Peninsula Medical School, "gives an air of precision to the prediction of future risk of disease that the science of molecular genetics cannot support". He adds that for conditions such as diabetes, hypertension and most common cancers, the conventional practice of estimating risk based on family history is more effective.
My own family medical history does not - so far as I know - hide any horrible secrets. None of my immediate family has died early and my grandparents all had reasonably good innings, except for my paternal grandfather who died of a heart attack in his 60s. But could the gene test reveal some hitherto unexpected defect?
Jenkins leads me into his lavish consulting room, sits at his desk and leans forward, framed by the massive carved fireplace behind him. This would be a rather intimidating way to receive bad news, I think to myself.
"We have a saying ... that the tea-leaves don't lie," he says. "Your genes are your genes, and yours are very favourable."
According to Genetic Health's analysis, I am at low or average risk of almost all the diseases the company has considered. For the genetic region linked to Alzheimer's - the test I was most worried about - I share my profile with 60% of the population so am firmly at average genetic risk. I do not have the best Alzheimer's genotype, but it is by no means the worst.
The relief is short-lived though when I show my clean bill of health to five leading experts. They describe the predictions and advice from Genetic Health as "poor", "flawed, "misleading" and "baloney".
"I am very sceptical about the scientific basis of this advice and think the public should be aware of the problems," says Professor Bruce Ponder, an expert in cancer genetics at Cambridge University.
Dr Paul Pharoah, a genetic epidemiologist at Cambridge University, agrees. "I think that there is little hard science behind most of what is claimed by Genetic Health." He says that for some of the conditions looked at by the company, they were simply looking at the wrong genes - ones with very flimsy evidence linking them to the disease.
"I would not regard any of the genetic variants they have tested as being associated with prostate cancer," adds Pharoah, by way of example, "[but] the genes that we know are associated with prostate cancer they just haven't tested."
McCarthy says that the variants chosen by the company linked to heart disease were mostly backed up by flimsy evidence that had not been replicated in later studies. "It seems quite bizarre to me, and potentially misleading, that customers are paying for a bunch of variants, many of which have questionable relationships with the diseases concerned."
When I tell Jenkins about the verdicts of the experts I had consulted he responds: "I would accept that it is an ongoing field and it is going to be for some time. It is science in its early stages." But he says that Genetic Health did respond to new developments and points out that the company tests for variants of the FTO and TCF7 genes which have been linked to obesity in large studies published in the past few months.
Meanwhile, Whitley says in Genetic Health's defence, that it is important, in general, to leave time for new research to bed down before applying it to patients. "You can't just offer a new gene. It would be totally irresponsible," he says, adding that unlike other companies, theirs offers a personal consultation with a doctor to help clients understand their results.
The experts also evaluated the health advice provided by the company. My report said, for example, "An interesting study showed that consumption of black tea (six mugs of black tea per day) significantly decreases the levels of good cholesterol (HDL) in ApoE3 carriers." That's me, so should I give up the tea? According to Hattersley, definitely not. This statement was based on a small study published 10 years ago in the British Journal of Nutrition. The
scientists who carried out the research billed it as a "pilot study" which involved just 65 people, and the reduction in HDL levels they measured was tiny. Using this as the basis for specific advice for patients is "a combination of bad science and pseudo science", he says. "These are unjustified dietary suggestions based on a very small and unreplicated study which is probably reporting a false positive result."
At my consultation, Jenkins gives me contradictory advice, "The consensus of all studies is that [green and black tea] are good and they lower one's risk of heart disease." When I point out this was the opposite of what was stated in my report he says he will clarify the information given out by the company in future.
Genetic testing is rapidly becoming big business, but in many countries - including the UK - companies have a virtually free rein over how they operate. Scientists and many in the industry, including Genetic Health, now say that better regulation is essential. Even potential commercial conflicts of interest go unchecked. In my report for example, Jenkins wrote: "if you remain concerned about your current propensity for lung cancer, you may wish to undergo a low dose CT scan of your lungs ... [European Scanning] employ one of the UK's most experienced lung specialists in the UK for interpreting the scans." The European Scanning Centre - which shares Genetic Health's Harley Street address - is cited as an affiliate company on Genetic Health's website and Dr Paul Jenkins is one of its directors.
Hattersley says selling services or products based on genetic tests is highly inappropriate. "These decisions should be made on the basis of clinical symptoms, clinical risk factors and simple first line clinical investigations like an ECG or chest x-ray."
"I would completely refute there is any hard sell," says Jenkins. "If somebody has an increased genetic risk of diseases then [a scan] is something I offer them. And sometimes people want it and sometimes people don't want it. It is entirely up to them."
Stuart Hogarth, a sociologist at Loughborough University and an expert on the regulation of genetic testing, likens the industry to a lawless wild west. "We made a huge public investment in the human genome project," he says. "It's not unreasonable that we need some kind of investment in a regulatory system that can make sure that the downstream clinical applications of the science are ... helping people rather than harming them."
