Contemporary classification of human disease derives from observational correlation between pathological analysis and clinical syndromes. Characterizing disease in this way established a nosology that has served clinicians well to the current time, and depends on observational skills and simple laboratory tools to define the syndromic phenotype. Yet, this time-honored diagnostic strategy has significant shortcomings that reflect both a lack of sensitivity in identifying preclinical disease, and a lack of specificity in defining disease unequivocally. In this paper, we focus on the latter limitation, viewing it as a reflection both of the different clinical presentations of many diseases (variable phenotypic expression), and of the excessive reliance on Cartesian reductionism in establishing diagnoses. The purpose of this perspective is to provide a logical basis for a new approach to classifying human disease that uses conventional reductionism and incorporates the nonreductionist approach of systems biomedicine.


Originally published in Molecular Systems Biology 2007, 3:124. doi:10.1038/msb4100163


genotype, complex networks, conventional reductionism

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Diseases, Phenotype, Pathology




EMBO and Nature Publishing Group

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This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 license (http://creativecommons.org/licenses/by-nc-sa/3.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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© 2007 EMBO and Nature Publishing Group

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