What's your profile?
The term `genetic profile' remains something of a myth. Mun Keat Looi looks at what yours could say about you
It has been five years since the Human Genome Project announced its rough draft. The field of genetics was supposed to have all the answers. Our DNA would be the great predictor of our lives, explaining our looks, our behaviour, our development and our evolution - at least that's what some quarters believed. But scientists still puzzle over the interaction of nature and nurture. Few traits are simply one or the other, and many are a headache-inducing mix of the two.
Genetic information, with its reams of statistics and webs of probabilities, is a confusing affair. There's a high probability of misinterpretation and endless potential for hyperbolic headlines. Still, the field continues to progress and the technology for genetic profiling gets cheaper, easier and more accessible. It won't be long before we can easily get our own, personal genetic profile. What would it say? What could you do with that information? Would you want it in the first-place?
In The mighty gene machine, conceived by the Graphic Science Unit at UWE, the Dana Centre presented these issues in a cringe-inducing play: a chat-show set 30 years in the future. This opened with "85 yearold Pierce Brosnan, the fastest man on a Zimmer-frame", but thankfully didn't go down that route and got straight into the main attraction: the gene machine. This newly created machine processes DNA samples in seconds, providing a full genetic profile and allowing the `studio guest' to reveal the host's real hair colour, musical ability and possible alcoholism.
Crude, but it did at least lay the groundwork for the interactive discussion. The audience was asked to rank different traits (risk of breast cancer, musical ability, risk of developing wrinkles, hair colour, Cystic Fibrosis) on a scale ranging from Genetic to Non-genetic. They mostly got it right, but failed to exactly nail the scale, missing the subtle influence of genes or environment on even the seemingly obvious factors.
Red hair may be clear-cut, but alcoholism is a blurry affair. Hair colour is genetic, but the sun bleaches it. Behaviour can be learnt, but there's always at least a partial influence of heredity. Gene expression can vary. And then there's the environmental influence. In a country where everyone smokes, genetics will have a stronger effect on the likelihood of lung cancer. But in a non-smoking country, the environment is the influential factor. Of course, nowhere is at either extreme. That makes guessing the balance so much more difficult. As Imperial's David Balding, Professor of Statistical Genetics, put it, "we are not genetic robots".
In case you hadn't guessed, genetics does not have all the answers. Or maybe it does, but we just don't know what they mean. "There's not much we can tell [from genetic profiles] at the moment", said Balding, "A lot of it is still unclear and there are many unknowns - even in twenty or thirty years, we still wouldn't understand everything; we think we're on the verge, but it just gets more and more complicated". He explained the concept of knockout mouse studies, where mice are developed missing a single gene. "A common outcome is that nothing happens. It's hard to say what one gene does because it often works in a complex way with others".
What we can do is diagnose genetic diseases, but some of them are still incurable. Would you really want to know that you'll develop Huntingdon's disease at the age of 50 - and can do nothing about it?
This lead to the second question discussed at the debate: who should have access to your genetic profile? Again, it seemed clear at first: your doctor should have access, your bank should not. Employers and the government most definitely not. But it becomes more complicated when you get down to the details. Returning to that incurable hereditary disease: you know you've got it, but should your doctor tell the rest of your family? Would they want to know? Couples with a history of hereditary diseases are encouraged to undertake genetic counselling and Pre-implantation Genetic Diagnosis (PGD) is now commonly used to screen embryos for potential problems. Good sense, you might think, but to some this is the equivalent of a biological pre-nup. If your spouse can look at your financial assets, why not the biological equivalent?
When insurance companies were mentioned, that really stirred the crowd. On the one hand, the very nature of the business is to assess risk based on the best predictive information available. They already use family history assessments, is genetic profiling so different? But does this open the gateway to new discrimination and an `uninsurable underclass'? As it stands, insurance companies have agreed not to use genetic information in insurance policies. But that moratorium runs out in 2011. Not so far away.
It comes down to a matter of personal privacy and trust. Most audience members were keen to have control over their genetic profiles. Yet only a quarter said they would want their profile in the first-place. I guess what you don't know can't hurt you. And besides, we wouldn't understand most of it anyway.
