Changes of tumor susceptibility arising concomitantly with a reversal of polydactylism in mice.

A change in susceptibility to tumor transplantation with the use of two sarcomas is reported in this paper to have arisen concomitantly with the sudden reversal in the penetrance of polydactylism in mouse//46801 of the Strong Polydactylous strain. Mice of the subline derived from #46801 grew the tumors in only 68 and 78 per cent of the cases, whereas the same subline without the polydactylism reversal grew the tumors in 97 and 100 per cent of the cases. Studies of 957 polydactylous mice in six divergent maternal age descents derived from a common origin showed no significant difference in susceptibility to tumor "takes" except in the one subline which showed the polydactylism reversal.