Black tabby (a.k.a.
"brown" tabby, ebony tabby-CFA Orientals, "bronze" - Egyptian Maus, "tawny
spotted", "ruddy"- Abyssinians, depending on breed and association) hairs,
showing smoothly colored tapering black tip (top), and even transition
to light warm color caused by the agouti gene. The picturesbelow
were taken through an Olympus AX-70 light microsope
at 40X with overhead illumination, on a white background, though it looks
Blue Tabby: The photo below, taken through an Olympus AX-70 light microsope at 100X on a white background with external overhead lighting as above overhead shows the typical irregular pigment distrubution caused by the dilute allele. The pigment itself is black as above, just irregularly deposited, producing a gray appearance to the naked eye. The region of the hair photographed is where the dark tip of the hair is going into the first light agouti band. Notice that the transition is not as even due to the irregular deposition of pigment caused by the dilute alleles.
Below, a light region of a blue tabby hair at higher magnification
Basic Color Genetics
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