The regeneration of triturus limbs deformed by a carcinogen.

In this study the regeneration of newt limbs deformed by carcinogen treatment was investigated. Treatment of an amputated limb with the carcinogen MNNG results in a regenerate with many abnormalities. Upon reamputation proximal to the first amputation level all new limbs regenerate normally, but when the reamputation is performed through the abnormal limbs the same type of abnormal limbs was regenerated. In cases of cone-arrested regenerates, reamputation within the cone does not results in regeneration. These results suggest that the carcinogen causes permanent changes in the blastema cells.