Posts Tagged ‘white-bellied hamster’

a. Wild-type golden hamster. b. Wild type hamster with that is heterozygous Wh. d. Homozygous Wh hamster-- anophthalmic or eyeless white. d. Heterozygous Wh and e/e hamster.

On Borderwars, there are many posts detailing the problems associated with breeding double merles and homozygous bobtails.

Of course, the problems with these sorts of lethal and deleterious semi-dominants are not confined to dogs.

Lots of other species have them.

My favorite case is a type of white that appears in golden or Syrian hamsters (Mesocricetus auratus).

There are four types of white in this species.  Three of them are of no consequence to the animals’ anatomy and physiology.  It is only the white hamsters that are white because of the Wh mutation that have problems.  Wh is inherited in a semidominant fashion. If a wild-type golden hamster is heterozygous for the Wh, it will have more white on its belly than it normally would.

And so long as the hamster is heterozygous Wh, it is of no consequence to the hamster.

But if one breeds two hamsters that are heterozygous Wh, you will produce 25 percent that are homozygous. Homozygous Wh hamsters will be solid white and have no eyes.

Hamsters in captivity really don’t need eyes.

I know that sounds shocking, but hamsters really don’t have to see things. If they can smell, they can find their way around.

But we have three other ways of producing white hamsters, so there really isn’t any good reason to produce them.

Unless we want to study them.

But the problem is that there are many hamsters that are white-bellied– that is they are wild type or some other color that are homozygous for Wh.

All wild-type golden hamsters have white bellies, so it can actually be hard to tell if a hamster is a true “white belly” or not.

And if you breed two of them together, you will get a theoretical 25% homozygous Wh– solid white with no eyes.




Read Full Post »

%d bloggers like this: