The Cream allele is very popular among horse breeders and horse fanciers alike. The Silver Brumby book series by Elyne Mitchell is about Palomino Brumbies living in the wilds of Australia, these books alone have inspired many with the love of the Cream allele. In America it was Roy Rogers and his Palomino horse Trigger that had many people falling in love with the Cream allele including creating a colour registry where only horses of the Palomino colour can be registered with.
Cream Allele Genetics
The Cream allele, also known as the Cremello allele, has been genetically studied and it is located on the MATP locus. Genetic testing for the Cream allele is available to the public. It is represented as a Cr when writing out a genome. The Cream allele is incomplete dominant. Due to it being an incomplete dominant gene it results in the largest group of colours when combined with the base colours (Extension and Agouti combos) compared to any other dilute gene.
Cream Allele Phenotype
The Cream allele dilutes red pigment far easier then black, in most cases it takes two Cream alleles to have a true affect on black. You can best see this on the Buckskin (E-A-Crcr), the body of red pigment is lighted easily however there is a larger contrast with the Black Points on the legs, mane and tail which have not been affected by the one allele. In some cases it is still easy to see the struggle to dilute black pigment even with two alleles present, you can see on some Perlinos (E-A-CrCr) who still have noticeable darker black points which are lightened to a beige versus the cream of the red pigment body. You can also see this when comparing Cremellos (ee–CrCr) to Smoky Creams (E-aaCrCr), the overall shade of theSmoky Cream is likely to be more of a mocha cream versions a very pale cream of the Cremello. With one Cream allele on a base coat with no other genes the horse will have black skin and brown eyes. With two Cream alleles on a base coat with no other genes the horse will have pink skin and blue eyes. The double Cream dilute blue eyes are often a pale baby blue and the pink skin is a darker pink; this especially true when looking at the pink skin caused by pinto genes which is lighter and the blue eyes which are darker/brighter. The pink skin makes them very sensitive to the sun for sun burns and are at a large risk for skin cancer. Rarely, double Cream dilute will have green eyes. Mottling can sometimes be seen on Double Cream dilutes skin.
Basic Cream Allele Colours
Below is a chart to help show what the basic colours of the Cream allele are. A basic Cream colour is when the Cream allele is combined with Extension and Agouti colours. On the left we see those basic Extension and Agouti colours. In the middle you will see the colour result for a horse with one Cream allele with the base colours on the left. On the right you see the results of the base colours with two Cream alleles. Due to the rareness of Wild Bay Agouti, I chose to make up possible names for the Wild Bay Combinations with the Cream allele.
Smoky Seal Brown – Smoky Brown, Sealskin
Seal Brown Cream – Brown Cream, Sealino
Check out the album to see pictures of Cream horses: