To our knowledge, only two AKC standards accept the harlequin pattern in their breed, and we’re pretty sure most of you will correctly identify the Great Dane as one of them. Can you guess the other?
From the Beauceron AKC standard: Gray, Black and Tan (Harlequin): Black and Tan base color with a pattern of blue-gray patches distributed evenly over the body and balanced with the base color, sometimes with a predominance of black.
We’d heard of the “Harlequin Pinscher, a strain developed in Germany that was recognized by the FCI in 1958, but as far as we 
know, the breed failed because of health problems. The entire breed was said to be made up of merles. All of them. As Scottie Westfall wrote in 2010: “The mistake was to breed for the merle coloration alone in the harlequin pinscher. There was a poor understanding of the need for outcross colors, and the potential for producing double merles with defects was simply too great”.
“Dante” in pastel by Dawn Secord
http://www.dawnsecord.com/DogArtGallery.html
Harlequin Beauceron image found on Pinterest and happily credited upon receipt of information
Speaking genetically, the harlequin Great Dane and the harlequin Beauceron are two different things. The Great Dane harlequin is Merle (PMEL17) plus a mutation at the Harlequin gene (PSMB71). The Beauceron is just Merle. A recent publication (Dreger et al. 2019, PLoS One) did find the Harlequin variant seen in Great Danes (PSMB71) also in Yorkshire terriers, though add a very low frequency. And because Yorkshire terriers do not have Merle, the harlequin phenotype wouldn’t actually show in them.
Excellent comment, D, thank you for rounding out the information on the Harlequin! The post is from our archives, and a lot has happened in our understanding of the genetics since the article was written four years ago!
In Australian Shepherds you’ll occasionally find a color pattern that was originally called harlequin, but was finally called tweed, so that it wouldn’t be confused with the Great Dane harlequin. It’s a variety of the merle pattern.
http://www.ashgi.org/home-page/genetics-info/faq/color-misc
Good stuff, Lynn, thank you! We’ll be collecting these comments and writing a post in the future that will be an update!
Isn’t there a Harlequin Newfie?
Not to our knowledge, Deloris, could you be thinking of a Landseer?
Collies have what we call the harlequin mutation in our merle gene patterns. They are just treat d as a merle be it sable merle or blue merle.
Interesting, Marcy! Thank you for sharing this information, it helps “round out” the discussion on harlequins
Can you breed two harlequin beaucerons ?
Sorry for the late reply, Alex, but we wanted to get you the most accurate information by consulting Beauceron breeders and vets. The resounding answer to you question is NO!!!! You should NOT breed two harlequin Beaucerons with each other.