High White and Harlequin: The Genetics of the ‘Van’ Pattern#

Most bicolored Maine Coons are “Tuxedos” or “Mitted”—they have white paws and a white chest. But recently, the High White look has taken the show world by storm. These are cats that are mostly white, with islands of color only on the head, tail, and perhaps a spot on the back.

This is the Van Pattern. It is named after the Turkish Van cat, but the genetic mechanism (the Piebald Spotting Gene) is the same in Maine Coons.

The Piebald Gene ($S$)#

White spotting is caused by the semi-dominant $S$ gene.

$ss$: No white (Solid).
$Ss$: Low to Medium White (Tuxedo, Lockets).
[cite_start]$SS$: High White (Van, Harlequin). [cite: 2945]

The 1-10 Grading Scale#

Geneticists grade white spotting on a scale of 1 to 10.

Grade 1-4 (Low White): Lockets, gloved feet, tuxedo bibs. [cite_start]Usually heterozygous ($Ss$). [cite: 2944]
Grade 5 (Bicolor): Roughly 50% white, 50% color. The classic “Cow Cat” look.
Grade 7-8 (Harlequin): Mostly white body with several large patches of color on the torso, legs, and head.
Grade 9-10 (Van): White body. Color is restricted only to the head (ears/cap) and the tail. [cite_start]This is the “Van” pattern, the Holy Grail of high-white breeding. [cite: 2944]

The “Melanoblast Migration” Theory#

Why does the color end up on the head and tail? Robinson’s Genetics explains that pigment cells (melanoblasts) migrate from the “Neural Crest” (the spine) during embryonic development. The $S$ gene slows this migration down.

The Result: The pigment cells don’t reach the toes or belly (creating white feet/tummies). [cite_start]In High White cats ($SS$), the cells barely make it out of the neural crest at all, surviving only at the “poles” of the cat (Head and Tail). [cite: 2945]

Conclusion#

A “Van” Maine Coon is visually striking because it combines the massive size of the breed with the stark, clean look of a white cat—but with a splash of color to show off the tabby or red genetics. It is a masterpiece of the $S$ gene.

References#

Vella, C. et al. (1999). Robinson’s Genetics. “Piebald White Spotting,” p. [cite_start]148. [cite: 2944]
Robinson, R. “White and White Spotted Cats,” p. [cite_start]146. [cite: 2945]
Walsh, L.G. (2013). The Maine Coon Cat. “The Colors of the Coon,” p. [cite_start]15. [cite: 1049]
CFA. Maine Coon Breed Standard: Bi-Color Division.