Saturday, April 27, 2013

Known unknowns

Philip Ball writes:

This week's diamond jubilee of the discovery of DNA's molecular structure rightly celebrates how Francis Crick, James Watson and their collaborators launched the 'genomic age' by revealing how hereditary information is encoded in the double helix. Yet the conventional narrative — in which their 1953 Nature paper led inexorably to the Human Genome Project and the dawn of personalized medicine — is as misleading as the popular narrative of gene function itself, in which the DNA sequence is translated into proteins and ultimately into an organism's observable characteristics, or phenotype.

Sixty years on, the very definition of 'gene' is hotly debated. We do not know what most of our DNA does, nor how, or to what extent it governs traits. In other words, we do not fully understand how evolution works at the molecular level.

That sounds to me like an extraordinarily exciting state of affairs, comparable perhaps to the disruptive discovery in cosmology in 1998 that the expansion of the Universe is accelerating rather than decelerating, as astronomers had believed since the late 1920s. Yet, while specialists debate what the latest findings mean, the rhetoric of popular discussions of DNA, genomics and evolution remains largely unchanged, and the public continues to be fed assurances that DNA is as solipsistic a blueprint as ever.

The more complex picture now emerging raises difficult questions that this outsider knows he can barely discern. But I can tell that the usual tidy tale of how 'DNA makes RNA makes protein' is sanitized to the point of distortion. Instead of occasional, muted confessions from genomics boosters and popularizers of evolution that the story has turned out to be a little more complex, there should be a bolder admission — indeed a celebration — of the known unknowns.

Read the rest here.

2 comments:

  1. That's an interesting, and good, article.

    Lots of good info in there regarding the current state of genomic research.

    Also instructive to see how the author is willing to cling to the old Darwinian paradigm of natural selection. At the front of the article he puts in the obligatory, "it is beyond serious doubt" but then much later he talks about how it isn't at all clear how natural selection at the phenotypic level can make it back down to the molecular level.

    That right there is enough to put the old paradigm on the table for discussion, but apparently not to the author.

    One can say, "We simply don't know yet how it works," and maybe that's true. In the meantime however, there is a serious disconnect between the level at which natural selection is said to act and the level at which phenotypes are determined.

    Seems to me like there is more than enough room for "serious doubt".

    PS: That article worked for me because I am currently on campus, but my wife ran into the paywall when she tired to access it from our house. Maybe post the PDF?

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    Replies
    1. Cool, thanks, Mr. Fosi. :-)

      I'll have to look into the PDF.

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