color genes B, C, D, G, H, I, M, S and T

color genes in dogs: the B, C, D, G, H, I, M, S and T loci

B: Brown series

This locus does not affect red colors.
 B = black
 b = brown (chocolate)
  In the Chow Chow only the allele B is present.

C: Color series

Research found that C is the gene tyrosinase. There is no variation in that gene in dogs, although there is variation in other species.

D: Dilution series

 D = intensive pigment
 d = dulition, dilutes black into blue and red into fawn (cinnamon)
  In the Chow Chow both alleles D and d are found.

Some researchers state that this locus only influences black color, but certainly in the Chow Chow there is a gene that dillutes the black and the red, either the D-series or an other (not yet located) gene.
Two of the blue Chow Chows that were tested on color have Dd, this supports the idea that there is an other gene that dillutes the Chow Chow coat.

G: Graying series

 G = the black hairs are graying with age
 g = no graying
  In the Chow Chow both alleles G and g could be present.

The G-series is not found yet in DNA, the presumed alleles are based on breeding results.

I: Intense series

 I = intense red, no dillution
 i = co-dominant, so ii is lighter as Ii
  In the Chow Chow are probably both alleles I en i present.

The I-series is not found yet in DNA, the presumed alleles are based on breeding results.

the loci H, M, S and T

H: Harlequin series
 H = the harlequin-pattern in the Great Dane
 h = no harlequin-pattern

M: Merle series
 MM = "defective white"
 Mm = the merle pattern.
 mm = no merle

S: Spotting series
 S = no spotting (solid color)
All other alleles give more or less spotting.

T: Ticking series
 T = ticking in the white spotted areas
 t = no ticking
  In the H, M, S and T series only one allele each (h, m, S and t) is present in the Chow Chow.

other possible loci

Red Chow Chows are often born with a black mask, in fawn pups this mask is blue. The mask fades away when the Chow gets older. Black and blue Chows could have the mask too, but because of their color it will not show. Cream Chows have no visible mask. The gene for a dark mask is E^M, as seen in Mastiffs and Pugs, but this mask does not fade away. So there could be a FM: Fading Mask series, or a not yet discovered allele at the E-locus.