Color: Harlequin is a coat pattern of distinctive dark spots on a white background.
Samples Accepted: Blood, Buccal Swabs
Locus Information: H locus: Harlequin is a coat pattern seen in many breeds with the merle color pattern, but officially recognized only in the Great Dane breed. Harlequin is a modifier of merle. All harlequin dogs have one or two copies of the mutation responsible for merle. Non-merle dogs can carry harlequin, but will not appear harlequin. A full explanation with pictures of dogs can be found on our collaborator’s website at the Clemson University Canine Genetics Lab.
Test Information: This mutation test identifies a single base pair change in exon 2 of the PSMB7 gene. Although Harlequin is dominant, it is a modifier of merle. Punnet squares of predicated outcomes for possible matings can also be found at Dr. Clark’s Clemson University Canine Genetics Lab website.
Clark, LA., Tsai, KL., Starr, AN., Nowend, KL., Murphy, KE.: A missense mutation in the 20S proteasome β2 subunit of Great Danes having harlequin coat patterning. Genomics 97:244-8, 2011. Pubmed reference: 21256207. Doi: 10.1016/j.ygeno.2011.01.003.
Further information is available at the Online Mendelian Inheritance in Animals website.