Please excuse my dust while I revamp this section
This gene determines if the color is extended all the way to the end of the hair shaft, or if the color stops at some point on the hair shaft and another color finishes. The non-extended hair shaft will produce colors such as black tortoiseshell (tort). The rabbit will appear shaded as shorter hairs near the belly, feet in muzzle aren’t long enough to show the color change in the hair shaft, where longer hairs will show the change. This gene can easily be confused with the C gene set as it will all produce shaded rabbits, but for a different reason. There are actually four genes in this gene set E – full extension of color, ES – extension of dark color, e – extension of light color, and ej. The ES gene produces various steel colors, and the ej gene produces harlequin color patterns.