The protein, called ALX3, could be an important regulator of stripes in other mammals, including cats and raccoons, says Michael Levine, a developmental biologist at Princeton University.
In the light stripes, the researchers found, the gene that produces ALX3 is much more active than in the brown or black stripes.
It wasn't clear whether the high levels of ALX3 caused the light stripes or not.
Previous pigmentation research failed to turn up ALX3 because researchers were working with white mice, Hoekstra says.
Eastern chipmunks (Tamias striatus), whose last shared ancestor with African striped mice lived about 70 million years ago, also made more ALX3 in the light stripes on their flanks, the researchers found.
The researchers still don't know how ALX3 production gets turned up in the light stripes.
A 15-year old boy presented with features characteristic of FND type I caused by ALX3 gene mutation, after the correction of severe hypertelorism, median nasal cleft with a broad nasal root and associated de-compensated intermittent exotropia with overaction of the inferior oblique muscles with V pattern.
Frontorhiny, a distinctive presentation of frontonasal dysplasia caused by recessive mutations in the ALX3 homeobox gene.