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April 29, 2010 -- Do you really want to know all of the information encoded in your genes? A thought-provoking new study shows why you might -- and why you might not.
It's not science fiction. It now costs less than $10,000 to learn your own personal genome. Soon it will cost no more than $1,000. What might you learn? Ask Stephen Quake, PhD, a Stanford University bioengineer.
Recently, Quake and colleagues showed that a whole human genome -- his own -- could be unraveled by a single technician using a single machine.
When a 19-year-old relative died suddenly in his sleep, Quake began to wonder whether the information he collected could tell him whether he risked the same fate. He took his genome to cardiologist Euan Ashley, MD, who runs Stanford's hypertrophic cardiomyopathy center.
"This made me start thinking about what doctors are supposed to do when a patient walks into your office, shows you his whole genome, and asks, 'What is in my crystal ball?'" Ashley tells WebMD. "It's a challenge. Lots of people have looked at human genomes, but nobody had ever looked at a single patient before."
Ashley and Quake assembled a large group of Stanford's top researchers. The group pored over all available information on genetic risk and then evaluated millions of the variations in Quake's genetic code.
In the end, it turns out that Quake carries three gene variants linked to sudden cardiac death. Genetic analysis shows he's at increased risk for heart attack, clogged arteries, type 2 diabetes, and some cancers.
Does this mean Quake is particularly unlucky? No. Because of the frequency of risk genes in the population, every single person who looks into their genome will find that they carry risk genes for more than one serious or deadly disease.
"It is all bad news," Quake tells WebMD. "After all, there is no genetic basis for happiness or athleticism. It's all about things that make you uncomfortable and ill. You have to have a strong stomach."
While it isn't what you'd call really good news, Quake did learn a number of helpful things. He's genetically more likely to respond to low doses of cholesterol-lowering drugs with a lower risk of side effects (in fact, he's begun taking the drugs even though he's only 40).
And should he ever need the drugs, Quake learned that he's less likely to respond to the blood-thinning drug Plavix than to alternative drugs, and he would need a lower starting dose of warfarin.
While there's always bad news from whole-genome sequencing, the fact that a person is at higher risk of a particular disease does not mean they're destined to suffer from it.
"The genome is not destiny. Many things have a chance to influence the outcomes," Quake notes. "There is a genetic component to risk, but there is an environmental component, too. For the vast majority of things about your health, your lifestyle choices and the environment you live in make equal contributions."