A Skeletal Difference Between Sublines of the C3H Strain of Mice

Abstract

Established in 1920, the C3H strain of mice has been used widely in research in cancer, physiology, and genetics for the last 25 years. In 1930 and in 1933 sub-lines were established, resulting in 3 main colonies (at Yale, Nat. Inst. of Health, and Univ. Minn.). Contrary to the suppositions of investigators working with them, mice of these 3 colonies are not alike, showing especially differences between numbers of thoracic and lumbar vertebrae; inferentially, other genetic differences may be present, invalidating strict comparison of research done with mice of different sub-lines. The cause and time of origin of the noted skeletal differences are unknown.