In case you missed it, there’s a dust-up in the online bioscience community about whether or not the Human Genome Project and genomic association studies in general have been worth the effort. While it’s great to debate whether gene sequences are helping humanity understand disease, they’re only a part of those convoluted processes, and it’s a little strange that’s not part of the conversation.
The latest salvo struck last week in the form of a Guardian column by Bioscience Resource Project Executive Director Jonathan Latham, ominously titled “The Failure of the Genome.”
Among all the genetic findings for common illnesses, such as heart disease, cancer and mental illnesses, only a handful are of genuine significance for human health. Faulty genes rarely cause, or even mildly predispose us, to disease, and as a consequence the science of human genetics is in deep crisis.
Read it yourself, of course, but the short version is that Latham disparages twin studies as a basis for concluding there’s a large genetic cause to common diseases, and he points out that only a fraction of diseases can be explained with genetic evidence. He cites this Francis Collins paper on “missing heritability,” and he’s got several good points on the subject. Then he gets a bit heated:
… The most likely explanation for why genes for common diseases have not been found is that, with few exceptions, they do not exist.
The failure to find meaningful inherited genetic predispositions is likely to become the most profound crisis that science has faced. …
Instead Latham would prefer research money spent on finding other causes, and since he’s a plant genetics guy working at a food- and agriculture-focused website, I’ll conclude he’s keen to investigate environmental factors. (Daniel MacArthur at Wired’s Genetic Future blog points out more explicit such advocacy by one of Latham’s co-workers.)
Anyway, critics stream through every portal. Among other critiques, Adam Rutherford, writer of BBC4’s the Gene Code, writes back in the Guardian that the Genome Project only started our current bioscience era, and that media reports often hype genetic findings.
Daniel MacArthur points out the Genetic Future blog post he wrote last year—where he responded to Latham’s previous version of this argument—saying that even if genes explain 19.6% of the human population’s diabetes risk, that says little about a person who definitely carries all the high-risk genes. A person with all those genes has a 41.3% risk of getting diabetes.
At Genomes Unzipped, Vincent Plagnol, Luke Jostins, and Daniel MacArthur (same guy) point out that scientists double-check twin studies, and they study heritability with other methods, anyway.
There’s much more to each one, but I can’t do justice to them all here.
But Latham’s not the only such critic, just the most recent. A previous round of genome-buyers’ remorse came last year from the New York Times’ Nicholas Wade and Andrew Pollack, the Wall Street Journal’s Matt Ridley, the Guardian’s Oliver James, and NPR’s Tom Ashbrook.
What’s odd about the public part of this debate is its “either-or” frame. Either we research genes or we research environmental factors. Either we cure diseases or we’ve wasted our time.
Brothers! Sisters! Come together! Of course environmental factors contribute to disease, and those studies are under-funded compared to Big Genetics. But as Genomes Unzipped says, genes aren’t all about disease risk. We have to understand what environmental factors do, and epigenetics is turning out to be a major link.
There’s age, obesity, exercise, and nutrition in helping to cause Type II diabetes through epigenetics. There’s early nutrition and a host of chronic diseases [pdf]. There’s epigenetics mediating environmental effects on neurodegenerative disease. And of course, the field of environmental factor-related cancer epigenetics only recently opened up.
It goes on and on. But it’s weird that virtually none of the discussions I linked above talk about epigenetics (well, Matt Ridley fumbles with it a little). It’s only in the comments section of that Tom Ashbrook radio show that anyone really brings it up–and not very well. Gene regulation and dysfunction are highly complicated, and it’s going to take more than 10 years with a decoded human genome to sort it all out.
(Flickr user dierken’s photo of cuckoo clock gears used under a Creative Commons license.)