Many people in the hamster fancy as well as many other rodent fancies have it in their minds that to
breed two related animals will result in things such as stillbirth, sickly animals, deformed animals, aggressive animals, etc. This has been a common misconception for years upon years. The fact remains that whether you realize it or not, to some degree, your very own hamster is most likely inbred. Unless a person goes out to the wild and captures their own hamster, chances are that you have a hamster from a breeder, pet shop, or another domestic source. Domesticated hamsters have been in the hands of breeders since 1937 when they were released to private parties from a London lab. The hamsters that were released were inbred from a single litter that was captured with the mother in Syria in 1930. Domesticated hamsters spread around the world from this original litter and another base stock was not shipped into North America until 1971 and even so, DNA studies have shown that all domestic stock in North America has come down from a single female which is believed to be the original 1930s female. Inbreeding is defined as the breeding of two genetically related parents. This definition is rather broad in that if one looks back on any given species, all are inbred several generations over, including the human species! What has more commonly become known as the definition of inbreeding is closer genetic relations such as brother/sister, mother/son, father/daughter, cousin/cousin, etc. Throughout history as well as in media and entertainment (movies, books, music…) we have been taught "inbreeding is bad". Not only from these sources but from our own bodies we have been taught through release of Oxytocin to recognize our family members as not acceptable for mating. Unfortunately, rodents and other animals do not function in the same way as humans and due to this, many of our social beliefs and actions tend to be projected onto them as if they function in the same way. They do not. Most animals do not have a hormonal trigger that clicks on to tell them that they shouldn't breed with their siblings, parents, or other relative. In many humans, this has also been found to be repressed or even missing! However, this is why animals are born to seek out the strongest, most capable of a species to breed with. Most capable may mean "most available" in many cases which is where we have cases of siblings mating or an offspring breeding with it's parent. The wonderful thing about this is that unless there are glaring genetic anomalies or health problems present, the resulting offspring tend to be just fine. A very bad stigma has been placed upon inbreeding and linebreeding due to many tellings and fictional stories. Some people would have you believe that breeding a single generation of brother/sister pairing would result in deformed, sickly, or even stillborn hamster pups! This just isn't the case. In fact, laboratories studies have been done in which brother/sister pairings have been done for upwards of 20 or more generations with little, if any, problems. Can problems crop up? Of course, they can, but that is where genetics comes in. When you breed two genetically similar (related) animals, you are essentially double stacking the genes of these animals. In any proper breeding program, you will be breeding animals that are the largest, strongest, healthiest, and if showing, most conforming to standard possible. That being said, you would not purposely breed an animal with a deformity, illness, or known temperament problem. If you are breeding two known to be healthy animals, there is little worry about stacking genes due to their already having known positive qualities. Even so, you have things such as recessive genes that may have negative effects that come into play. Just as stacking good genes can happen, stacking bad can happen equally. I have mentioned the term "linebreeding" several times in this posting thus far and it is for a reason. Linebreeding is not as simple as mating related animals. Linebreeding is a carefully calculated method of selectively breeding related animals to achieve certain goals and results. Such goals can be to remove a bad trait from a line, isolate a specific gene that is defective, and to overall improve the line/species as a whole. By weeding out the bad genes, you essentially create a better animal overall that will have a healthier, happier, and in many cases, longer life! Linebreeding IS NOT done because one does not wish to purchase new stock. Many ill-informed breeders learn the term "linebreeding" and use it to gloss over bad breeding habits. Unfortunately, this is a problem that adds to the already stigmatized thought of inbreeding. So, to summarize…
Most, if not all, hamsters that are domestically available have come down from the same mother and litter which was extensively linebred for study.
Inbreeding and linebreeding can be quite beneficial when undertaken properly.
You will not instantly find yourself in the possession of sick, mean, deformed, or stillborn pups from a single generation of pups born to a brother/sister pair.
Inbred hamsters do not live unhealthier or shorter lives than hamsters bred to constant outcrosses.
Linebreeding and inbreeding, when done properly can be very beneficial to any breeding program and can produce healthier animals overall. The problems arise when you have little knowledge of your animals’ genetics and the bad genes start stacking up. These are the cases where you find things such as poor immune systems, deformities, blindness, and other abnormalities.
Leave the breeding to those that are willing to do the research and go the extra distance to ensure not only healthy hamsters, but if you do find yourself with an unintentional litter, don't panic! Even if you have a pair that are siblings or related, there is little to worry about other than raising the pups to the best of your ability!
Remember, the only way people become educated is by sharing GOOD information. If we allow these myths and stigmas to continue it does nothing for the hamster community, owners, future research, or the hamsters themselves.
In closing, if you find that you do have an inbred hamster, enjoy them! They are just like any other hamster regardless of parentage! As long as you love them and give them the best home and life possible, that is what REALLY matters.
If you are interested in reading up further on this controversial subject, I have assembled some links for your viewing pleasure: