Horse Coat Color Modifiers There are several different modifying genes which can have an effect on coat color. Grey About the grey modifier Bay About the bay modifier Seal Brown About the seal modifier Mealy/Pangare About the mealy modifier Sooty/Smutty About the sooty/smutty modifier Flaxen About the flaxen modifier More Colors Colors | Base | Modifiers | Dilutions | White Patterns | Rare | Markings