Biomedical Engineering Reference
In-Depth Information
at their glass-jar-encumbered lab benches and the consortium team
leaders in late twentieth-century casual attire, coiffed with headphones
linking them to teams of computer geeks annotating the cascade of data
flowing from Celera's array of imposing sequencing machinery. In sum,
“The Drosophila Genome” issue of
Science
contains much matter to
ponder for geneticists and nongeneticists alike.
5
And of course, it won't
be long before
Science
publishes its special issue on “The Human
Genome.”
One of the elder statesmen of genetics, the wise and witty Sydney
Brenner, in a trenchant summary piece preceding the Drosophila genome
map aptly titled “The End of the Beginning,” brilliantly frames the sig-
nificance of the current conjuncture in genetics. Brenner, himself the
leader of the project to map the worm,
C. elegans
, opens his
Science
article by observing that “in classical experimental genetics, we could
not assert the existence of a wild-type gene until a mutant version with
an altered function had been isolated” [a series: one gene, one function,
one phenotypic difference]. “But,” he continues, “if one asked how many
genes were required to make a bacteriophage or a bacterium or a fly or
a mouse, no answer could be given.”
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Classical geneticists could never
have produced “The Drosophila Genome” special issue because although
they had developed techniques to isolate and map genes (in fact, decades
before anyone knew what genes were biochemically), classical genetics
had no concept equivalent to what is today called a genome. Conse-
quently, and not surprisingly, there were neither the experimental systems
nor the technologies yet invented that might have provided an answer to
a question that had not been posed: What is a genome? The full impact
of this conceptual shift in our understanding of living beings has perhaps
not yet achieved an adequate place in public understanding given all the
attention that the media have lavished on the gene for this, that, and the
other thing, as well as such hot-button issues, seemingly rife with epochal
significance, such as patenting life, cloning humans, and genetically mod-
ified foods. In fact, the gene for this, that, and the other thing probably
should have been seen as one of the last triumphs of what Brenner calls
“classical genetics” (remember, it used to be called modern genetics)
rather than serving as the herald of the dawning of the new genomics.
Consequently, it is eminently worth underscoring Brenner's point that
locating genes is not the same thing as mapping genomes. All involved
