B-Locus (Black/Brown)

Genes: B b
The Black/brown ("B") gene set has two possible genes. They are listed in order of dominance: B and b. The B locus is responsible for making a rabbit either black based or chocolate based. There are only THREE different gene combinations for the B Locus: BB, Bb, and bb.

B: BLACK

  • Most dominant gene, dominant over b.
  • Common varieties of B: chestnut, opal, black, blue, chinchilla, black otter (blue rabbits are “black” based)
  • Possible gene combinations of the B locus with B as the dominant gene: BB, Bb

​Rabbits with B as the dominant gene are black-based rabbits and will not express chocolate.
Picture
Broken black (B_) vs broken chocolate (bb)

b: BROWN/CHOCOLATE

  • Most recessive, recessive to B.
  • Common varieties of b: chocolate, lilac, amber, chocolate otter, chocolate chinchilla (lilac rabbits are “chocolate” based as well)
  • Possible gene combinations of the B locus with b as the dominant gene: bb

Rabbits with b as the dominant gene are chocolate-based rabbits and will not express black.

On to the "C" Gene...