W34, a white-spotting allele identified by researchers at Etalon Diagnostics in 2022, has been confirmed as present in the Paint Horse population. The discovery was published in the August 2022 edition of Animals, a peer-reviewed scientific publication.

This spotting pattern is a mutation of the KITgene, which is also home to Sabino 1 and more than 30 “W” (formerly, Dominant White) mutations that can cause white spotting patterns. W34 tends to produce white markings on the face and legs.

Along with other white-spotting patterns—which include Tobiano, Frame Overo, Sabino 1, Splashed White 1/2/3/5/6/7 and W5/10/20/22/31/32—W34 can be used to help a horse earn Regular Registry status as part of RG-070.E., an APHA rule that allows a horse to earn Regular Registry status if it meets requirements including presence of a Paint trait(s) and a white spotting-pattern gene confirmed through DNA genetic testing.

DNA testing for W34 is offered at APHA partner lab Etalon as an a la carte option.