Hey you folks good with genetics - Page 1

I know of a litter coming up, mother deep red/very dark black west german female, very excellent pigment, sire is sable working line dog. What colors can they get there? I've seen blk/red bicolors with one sable/one blk.red parent (bi-color grandparent) and I've seen work/show crosses that were sables but with light black ticking and very red undercoat. How do these kinds of genes work, and what can they expect to get?

Keep in mind all three coat colors you have mentioned are dominant: blk/red, sable, bi-color (bi-color usually comes into play when black is present in the lines somewhere). So, the potential is up in the air what exactly will happen. You may see blk/reds, may see sables,or  a combination/variation of the two dominant coat colors in one litter (depending on which parent seems to be more dominant when it comes to coat color genetics). You may occassionally see bi-color but the chances aren't near as strong to see bi-color as it is the other two. Do you know if either dog is proven and seems to throw their particular color strong when being bred similar to what you're describing with other partners prior to this breeding? That might help give a hint into things also. There's a 50/50 chance each pup to be blk/red or sable with such a pair-up. It depends on which parent proves stronger in dominance in the coat color factor in the breeding. One cannot be 100% sure until pups are born and seen.

If the sable sire has alot of black in his pedigree background and he produces sable pups with the blk/red female, then the sable pups could have the black guardhairs with the red undercoat like you described and darker masked faces. Or if there's alot of sable behind him, he could produce sables with more of a reddish tan (I would look for the male pups to be richer in pigment coloration than females in all cases) and decent masked face. If blk/red pups are produced, some could turn out with more of a sable ticking thru their saddle and along the spine, which won't be identifiable until the pups are about 7-12mos old. Or you could get blk/red pups with noapparent indicator the sire is sable, but those are definite carriers of the sable coat color. If you got bi-color, it would be determined upon how much black is in the sire's background, but probably won't be a dark bi-color (almost black) due to the mother being a traditional blk/red.

Genetics are amazing in that, from breeding to breeding, you never know just exactly what you may get. One breeding between the two descripbed may produce all blk/reds. Another time, all sables.  Another time 1/2 and 1/2. And another litter may produce one bi-color in it. It's just all up to what happens when sperm and egg join.

Color genetics is very simple.

Sable is the dominant color trait in GSDs.  Period.  If the sire is a homozygous sable (got a sable gene from both parents), then all pups in the litter will be sable.  No ifs, ands, or buts.  However, if he is a heterozygous sable (one sable gene from one parent, one other color gene from another parent), then only part of the litter will be sable.

Black & Brown is the next in line in dominance.  Red is just a pigment modifier and not directly on the color gene.  So, if the sire is heterzygous sable and his other color gene is Black & Brown and the female is Black & Brown, then you can expect the majority of the pups to be Black & Brown.

Bicolor is 3rd in line for dominance.  So, if the female and male both have the bicolor gene (keeping in mind that their dominant colors are Black & Brown for the female and sable for the male), then you might see some bicolor pups.

Black is the recessive color gene.  Both parents must carry it and both must pass it on to a pup for it to manifest.  There is some chance (and we do see it from time to time) of incomplete dominance of another color trait that allows the black gene to partially express itself.  You'll see pencil marks on the toes, black on the legs, etc.

White is a masking gene.  If a dog is white, then both parents contributed the masking gene.  The dog is actually another color, however the color is not allowed to manifest itself because it is masked by the double white gene.