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Revolutionary ideas come round again


Plus çà change. Editorials in Nature1,2,3 pointing out that the studies of many molecular biologists have been largely qualitative are one thing, and very welcome. However, it is quite wrong to comment3 that “the biologist ⃛ will probably have had very little quantitative training”, since at least those biochemists who deal with enzymes and metabolism must of necessity work properly with numbers.

The post-genomic era will certainly be characterized by large-scale and quantitative analyses, but it is the large scale that is new, not the quantitative aspect. Sensitivity analysis, which is what Alon et al.4 have done, has been a tool of biochemistry for a quarter of a century5,6,7. Robustness and rigidity against large changes in fluxes following changes in enzyme levels are a well-established property of metabolic networks8 that follows naturally from their structure and kinetic properties9.

But etymologically you are correct; if quantitative methods in biology are a “revolution” it is only because they are coming round again.


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Kell, D. Revolutionary ideas come round again. Nature 397, 644 (1999).

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