Genetic studies of the Syrian hamster III. Variation of dermal pigmentation

Summary An inherited modification of the dermal pigmentation of the Syrian hamster is described. The distribution of this pigmentation is variable in the normal hamster, especially that in the region of the genitalia of the male. However, the variation described here surpasses in extent this usual variability and, in particular, either partially or completely removes pigment from the ear pinna. This part was chosen as representative of the modification in general. The inheritance may be monogenic, with considerable impenetrance or, as may be more probable, may be polygenic. The complete suppression of pigment may be the consequence of the time of onset of the modification.