The Effects of Genetic Background of Mouse Models of Cancer: Friend or Foe?

Over the past century, mice have been selectively bred to give rise to the strains used in biomedical research today. Mouse models of cancer allow researchers to control variables of diet, environment, and genetic heterogeneity to better dissect the role of these factors in cancer in humans. Because of the important role of genetic background in cancer, the strain of the mouse can introduce confounding results in studies of mouse models if not properly controlled. Conversely, genetic variation between strains can also provide important new insights into cancer mechanisms. Here, the sources of genetic heterogeneity in mouse models are reviewed, with an explanation of how heterogeneity modifies cancer phenotypes.