25 April 2011

In which I unzip a few genomes...

Here is a post I made by way of comment on "Genomes Unzipped". Enjoy!

Elmatos, while those posts are strong on passion, they are weak on
coherence. I am a clinical geneticist, and I deal with hundreds of
families every year where the genome very much *has* delivered, and
keeps delivering. We would not currently have NGS devices/services (is
the distinction even relevant any more?) were it not for the human
genome project, and by the sound of it you wouldn't even have a job!
Think of a lot of this research money as stimulating/subsidising the
development of a new industry sector. Your boss has it all wrong if he
thinks everyone will need a sequencer. What we *need* is the
*sequence*. Your genome is essentially a big chunk of data (actually
not that big - just over a CDROMful) that you could as easily carry
around on a USB stick or upload to a server. NGS is simply a way of
getting past a firewall set by biology.

But that is what this is all about - it is not about "finding cures in
the genome" (I really don't think anyone working in the field for the
last 20 years has been anticipating this, despite the breathless hype
of the journos). It *is* about understanding the *biology*, and that
is paying off in spades. We are finding out how the human organism
functions. Genes are not "magic", nor are they "building blocks", and
they certainly aren't "for" anything directly. But thanks to our
developing understanding of the genome(s), we are putting together
some very powerful explanatory frameworks for getting to the bottom of
the biology of disease.

Now, I'm a clinical geneticist, yes, and I don't have a heck of a lot
to offer my patients other than a diagnosis and the phone number of
another family facing the same situation (actually, I underplay my
hand here - there is often a lot we can do, and this is improving all
the time). But when you tell the parents of a 20 year-old girl with
severe learning disability and epilepsy that she has a de novo
mutation in TCF4 and a diagnosis of Pitt Hopkins syndrome, after a
lifetime of the mother blaming *herself* for causing this, and
panicking over the possibility of it being transmitted to her other
children's children, then you see that knowledge itself is of real
therapeutic value.

And so the feck what if the diseases are "rare"? Rare diseases are the
natural experiments by which we have unpacked a phenomenal amount of
human biology that is directly relevant to "common" diseases.
Furthermore, there are more people collectively with "rare" disorders
than there are with most "common" conditions. And as if that weren't
enough, "rare" disorders are almost invariably more common than you
realise, and "common" disorders are almost invariably rarer.

Genomics is helping us to break down that firewall and manage genetic
information in much the same way as other digital information; sure,
we need to know how to interpret it, but we are not nearly as ignorant
of its import as many people (such as Latham) imply, and, perhaps more
importantly (and fatal to the doom-mongers' lamentations) there is no
sign of this slowing down. The advances are real, and they are
delivering *now*, just perhaps not in the way that some people in
their simplistic and medically uninformed analyses wanted them to.

-@shanemuk http://answersingenes.blogspot.com

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