The term abstract refers to dogs with less than 50% white on any solid colour. This includes white patches on any or all of: feet, chest (tuxedos), chin (milk chin).

 

An abstract marked dog carries 1 parti gene. A tuxedo marked dog carries 2 parti genes.

 

S locus alleles (or MITF gene) determine the degree and distribution of spotting. Parti dogs have a MITF gene that causes large patches with no colour.