The quest for Genetic health, and understanding the genes themselves, are a little like reading an engineering blueprint - undecipherable, unless you know the "language". There are hundreds upon hundreds of genes contained in a single dog - and even more combinations possible, with those genes. And we are far from knowing everything there is to know about genetics, and most of the tests we have currently are not yet perfect.


    Back in the days of the "Oldtimers", genetic testing was a thing of the future, and breeders had little choice but to "experiment" with their breeding programs. They observed the results, and then proceeded accordingly. If a "problem" presented itself, all they could do was avoid that particular pairing of dogs in the future. And considering where we are today, with purebreds, they did pretty well.


    Despite what is commonly said, purebreds are NOT high strung in temperament, or genetically unhealthy due to their breeding. Purebreds are *predictable* - when you buy a Labrador, you know what it will look like, approximately how big it will be, and what it will be like in personality. And you know these things *because* it is a purebred.


    Genetic problems are in the genes, not the breeding. These conditions and tendencies have always existed, and they're most assuredly present in mixed breeds, just as they are in purebreds. The difference is that with the practices in use in breeding purebred dogs (line and in breeding) these problems become "visible" - we find out they're there.


    Now why would we want to breed in a manner that will bring these problems to light, and sometimes cause suffering in the animals affected? Because by finding out where these problems are, which bloodlines may be producing more than their share of them, we can figure out how to breed *away* from those combinations that seem to cause more problems - and breed *healthier dogs*. And this is the goal of all reputable purebred breeders.


    With our current level of genetic technology, we can pinpoint and eliminate many problematic genetic combinations, by identifying the presence of the problem genes in a given dog, and not breeding that dog. But we are not yet to the point that all of these tests are fool proof. Many of these tests can only indicate that a problem may be present - or that a dog has a problem, but not the precise genetic combination that caused it.


    The mode of inheritance has a great deal of affect on whether or not we can actually eliminate a problem, or if we can only try to avoid it. A simple dominant can be selected against, but a recessive gene, or the "poly gene" (meaning multiple genes) is very much less easily eradicated.


    Now, the following is only my personal opinion, and I'm not a geneticist. But it appears to me - for instance - that hip dysplasia, a condition that is suspected to be polygenetic in inheritance (as well as affected by environmental aspects) is not only present in most breeds, especially large breeds, but that it will not be eliminated until we actually have the technology to identify each gene present in the combination it takes to create the condition of dysplasia. Until that point, we can only test for the *presence* of the condition in a dog - not the exact genes that caused it, nor can we actually predict which dogs will produce it. We can avoid using a dog that has the condition, and we can avoid using the combination of bloodlines (the pairing of sire and dam) that produced it in offspring. We can avoid using individuals related to a dog that has the condition. But we can't eliminate the thing - not yet.


    I say this because it is known that dogs who have been x-rayed free of the condition have produced it in their offspring. This is the nature of polygenetic inheritance : it takes the correct *combination* of a number of genes to produce a condition, and the higher - or lower - the number of the correct genes there are, determines just how affected the animal will be. A dog with fewer of the necessary genes may not even appear to be dysplastic. A dog with a higher number of the needed genes may be completely crippled by the age of two. So, my "take" on genetic testing? Without doubt, it is a *great* tool. But it is not yet the whole answer.


    For those problem genes that have been identified, for which there are actually tests that identify the culprit gene, then yes, testing is a "must". But for those genetic problems that don't yet have tests that actually identify the genes themselves, testing is, at best, akin to using a table knife in place of a screwdriver - It works pretty well, but the screwdriver is better. In other words - be aware, as you search for that "perfect pup", that although we breeders advertise that we test for this or that, we can rarely actually *guarantee* that we will never produce it. Right now, for most genetic troubles, we've only got a table knife at hand...


    So, the breeder who tests is a good breeder, yes. But the breeder who doesn't, isn't necessarily a bad breeder. Learn what you can about the breed you seek, learn what genetic ills may be present - and learn the nature of those ills, so that you can fairly determine whether the problem is one that the breeder truly can eliminate - or if it's one that they can only try their best to avoid. And please don't fall for the 'old saw' about mixed breeds being healthier. These problems are in the genes - and 99.9% of all mixed breeds are some combination of pure breeds! This means that mixed breeds are no more immune to genetic ills than purebreds are.


    There are only two basic reasons for the appearance of better health in mixed breeds : 1) genetic testing of mixed breed pets is rare, so that if problems are present they're rarely ever identified ; and 2) as stated above the practice of breeding purebreds does NOT create bad genes, it simply combines and intensifies the genes that are already present, which can illuminate the presence of problematic genes either through visible expression or testing - and because breeders of purebreds DO test for these problems it creates the appearance of health problems in purebreds as being more prevalent.


    Genetics 101 : Genes exist in an organism, they are passed down through generations from parent to offspring, they are not created by any breeding practice. The practice of mixing breeds only creates the illusion of good health - in reality this practice is simply spreading those already existing genes further and further through the population. Until we have genomes mapped out with identifying 'flags', the practice of purebred breeding is actually the best 'tool' available for identifying and attempting to eliminate genetic ills. This is true for anything living and breathing that has genes and procreates.


But don't take my word for it - be responsible enough to investigate genetics for yourself!

The information highway is multi-laned and unending and it's right at your fingertips :).

 

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