A friend of mine told me recently her vet said that if a dog is a crossbreed, and it is 1/2 labrador, the dominant gene is the lab. Is this true? My puppy is a Golden Retriever and Black Labrador Retriever, so which is dominant?

A puppy takes half its genes from each parent. So your pup is half Golden and half Labrador. It is down to chance which of the various genes will be dominant over the others, according to how the DNA 'soup' has been passed to your individual puppy. The other puppies in the litter will all be different, too.

Completely agree with Jeangenie. There is no way of knowing which of the two breeds it will take after.

A puppy inherits a set of genes from each of the parents and becomes the sum of the two. If a gene for a hereditary problem, say PRA for example, is present in one set but not the other then the ailment will not show up in that puppy but it would still be a carrier. If the sire and dam, as in this case are not of the same breed then even if both carry the gene for PRA the puppy would not suffer from it because as they are different breeds the gene will not be in the same place in the two sets of the genome! BUT, the puppy WILL now be a carrier of BOTH examples of PRA and if mated to a carrier of either of the breeds then the puppies could then develop PRA.

This is the reason why crossbreeds "Seem" more healthy. Unfortunately, if a crossbreed is mated to another crossbreed of the same two breeds then it could be less healthy than a full pedigree because it would then be open to all hereditary problems which afflict BOTH breeds!

Regards, John

Gosh you don't half explain things well John :-D
Anne

Too clever for my own good Anne! When i read it again it diddn't make sense so I've changed it slightly.

Best wishes, John