We are all individuals: causes and consequences of non-genetic heterogeneity in mammalian cells

Curr Opin Genet Dev. 2011 Dec;21(6):753-8. doi: 10.1016/j.gde.2011.09.010. Epub 2011 Oct 15.


The human body is formed by trillions of individual cells. These cells work together with remarkable precision, first forming an adult organism out of a single fertilized egg, and then keeping the organism alive and functional for decades. To achieve this precision, one would assume that each individual cell reacts in a reliable, reproducible way to a given input, faithfully executing the required task. However, a growing number of studies investigating cellular processes on the level of single cells revealed large heterogeneity even among genetically identical cells of the same cell type. Here we discuss the sources of heterogeneity in mammalian systems; how cells ensure reliable processing of information despite fluctuations in their molecular components; and what could be the benefit of cell-to-cell variability for mammalian cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Cell Physiological Phenomena*
  • Genetic Heterogeneity*
  • Humans
  • Models, Biological
  • Signal Transduction
  • Systems Biology