Does a sister dog need testing

[Elizabeth Hagio]

I've come across a breeder that has has her dogs tested. Her most recent dog that was breed was not tested. They didn't test her stating that her sister is healthy so she is rules out by full sisters clean bill of health. Is that true?

[Karen, Jasper and Jackdoodle]

No it's not true, and I would run far from this breeder. You don't have to study genetics to know that all siblings do not get the same combination of genes from their parents, and all dogs in a litter do not get the exact same combination of genes from their parents, either. I know many people who have a sibling with a genetic disease, and they don;t have it. I also know many dogs who have gotten various genetic diseases and conditions and their littermates are perfectly fine. Every dog with hip dysplasia doesn't have siblings who all have hip dysplasia, too. Either this breeder is ignorant about genetics or she's cutting corners and giving you false information; either way, run. 

[F, Calla & Luca]

Amen.