▁that ▁identified ▁the ▁nature ▁of ▁cre am ▁dil ution ▁was ▁directly ▁supported ▁by ▁bre ed ▁reg ist ries ▁that ▁had ▁histor ically ▁bar red ▁blue ▁e yed ▁cre ams . ▁ ▁C rypt ic ▁cre ams ▁The ▁cre am ▁gene ' s ▁prefer ential ▁effect ▁on ▁red ▁p ig ment ▁has ▁not ▁yet ▁been ▁explained . ▁The ▁champ agne ▁dil ution ▁affect s ▁both ▁black ▁and ▁red ▁p ig ments ▁equally , ▁the ▁silver ▁d apple ▁gene ▁affect s ▁only ▁black ▁p ig ment , ▁and ▁p ear l ▁exhib its ▁a ▁re cess ive ▁mode ▁of ▁inheritance ▁and ▁only ▁affect s ▁red ▁p ig ment . ▁Un like ▁the ▁cre am ▁gene , ▁p ear l ▁does ▁not ▁seem ▁to ▁affect ▁the ▁man e ▁and ▁tail ▁to ▁a ▁greater ▁extent ▁than ▁the ▁body ▁coat , ▁a ▁feature ▁of ▁cre am ▁that ▁is ▁most ▁v ivid ly ▁illustrated ▁in ▁the ▁pal om ino ▁coat ▁color . ▁This ▁characteristic ▁of ▁the ▁cre am ▁gene ▁is ▁also ▁un exp la ined . ▁The ▁dispar ity ▁in ▁effects ▁on ▁red ▁and ▁black ▁p ig ments ▁is ▁easy ▁to ▁identify ▁in ▁bu ck sk ins , ▁with ▁their ▁black ▁points , ▁but ▁it ▁is ▁also ▁visible ▁in ▁CC r / CC r ▁hom o zy g otes : ▁per lin os ▁( hom o zy g ous ▁cre am ▁on ▁a ▁bay ▁coat ) ▁often ▁retain ▁points ▁that ▁are ▁a ▁dark er ▁sh ade ▁of ▁cre am . ▁▁ ▁This ▁unusual ▁feature ▁enables ▁what ▁are ▁called ▁crypt