Exploiting cellular-developmental evolution as the scientific basis for preventive medicine

Department of Pediatrics, David Geffen School of Medicine, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, Los Angeles, California 90502, United States.
Medical Hypotheses (Impact Factor: 1.07). 02/2009; 72(5):596-602. DOI: 10.1016/j.mehy.2008.09.057
Source: PubMed


In the post-genomic era, we must make maximal use of this technological advancement to broaden our perspective on biology and medicine. Our understanding of the evolutionary process is undermined by looking at it retrospectively, perpetuating a descriptive rather than a mechanistic approach. The reintroduction of developmental biologic principles into evolutionary studies, or evo-devo, allows us to apply embryologic cell-molecular biologic principles to the mechanisms of phylogeny, obviating the artificial space and time barriers between ontogeny and phylogeny. This perspective allows us to consider the continuum between the proximate and ultimate causes of speciation, which was unthinkable when looked at from the descriptive perspective. Using a cell-cell interactive 'middle-out' approach, we have gained insight to the evolution of the lung from the swim bladder of fish based on gene regulatory networks that generate both lung ontogeny and phylogeny, i.e. decreased alveolar size, decreased alveolar wall thickness, and increased alveolar wall strength. Vertical integration of cell-cell interactions predicts the adaptivity and maladaptivity of the lung, leading to novel insights for chronic lung disease. Since we have employed principles involved in all of development, this approach is amenable to all biologic structures, functions, adaptations, maladaptations, and diseases, providing an operational basis for preventive medicine.

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Available from: Virender Rehan, Aug 04, 2014
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    • "We have previously shown that viewing lung ontogeny and phylogeny from the common denominator of cell-cell interactive paracrine signaling reveals that they are one and the same mechanism of morphogenesis, suggesting that time is superfluous to understanding vertebrate evolution (Torday and Rehan 2009a, 2009b, 2009c). The time variable is an artifact of descriptive biology. "
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