|A Black-eyed Argente baby (abbreviated BEA and with the genetic symbol bb) born to two BEA parents showed odd coloring with brindling (heavy black tipping in stripe-like patterns). I paired this brindled baby with her brother and sister ? littermates ? both of whom were typical BEAs. As they started having babies, the brindled BEA had all normal babies. Her BEA sister had all BEA babies.
Hoping that this was a recessive pattern and would turn up in her normal babies (who, because of their BEA father were Bb), I put together a trio of her normal babies. These normal babies produced the appropriate 25% BEA babies that would be expected from BEA carriers (Bb). No brindled or otherwise interesting babies appeared in their litters.
There were never any other brindled babies born in any of the litters discussed above. I concluded that this was not a gene mutation but was instead a cell mutation in that particular BEA.