Somatic Cell Genetics in the Analysis of in Vitro Senescence

  • Thomas H. Norwood


The limited replicative life span, or “senescence,” of cultured human diploid somatic cells is now well established (Hayflick and Moorhead, 1961). During the past decade, extensive investigations have resulted in detailed characterization of these cells; the mechanism or mechanisms that regulate their limited proliferative capabilities, however, remain unknown. Moreover, the relevance of such in vitro senescence to the aging of proliferating cell populations in vivo is controversial. Indeed, the relative contributions of proliferating cell populations and postmitotic cells to the aging process are also unknown. There is no information that clearly favors one or the other of the various hypotheses concerning the mechanism of senescence in the intact organism. Thus, while we are in this state of relative ignorance, it is important to analyze all potentially relevant model systems with a variety of experimental approaches.


Senescent Cell Sister Chromatid Exchange T98G Cell Xeroderma Pigmentosum Hybrid Clone 
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Copyright information

© Plenum Press, New York 1978

Authors and Affiliations

  • Thomas H. Norwood
    • 1
  1. 1.Department of PathologyUniversity of WashingtonSeattleUSA

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