by Sunsilver on 05 April 2020 - 16:04
Franka's mutation is DOMINANT. If the dog doesn't show Panda markings, it does not have the gene. Franka is heterozygous for the Panda gene (only has one copy of it) so she did produce dogs with normal markings when bred.
As far as I know, the only other source of such extensive white spotting is the 'S' locus. When Franka's genes were examined, they would have been able to see if she had that particular gene, which does not occur in German shepherds.
Yes, I am SURE the would have looked for it!
You have to understand: genetics has become a VERY sophisticated science these days.
They even know exactly which amino acid is missing from Franka's DNA to cause the mutation.
I am also sure that at some point SOMEONE did basic genetic testing on these dogs to make sure they WERE purebred! That would have been the first step any decent breeder would have thought of. Even if that wasn't done, I'm sure the detailed genetic analysis done by the university would have spotted any non-GSD genes.
by Rik on 05 April 2020 - 16:04
SS, this is what I was calling a BC type color/pattern. not saying at all that there was a BC in the wood pile.
I guess it's possible the dog"s parents both carried black recessive and then the white color splashing,
I grew up with lots of horses, and saw several paints with the "eye" you describe. we called them "glass" eye because most were very, very light in color.
that is certainly a resonable explanation for the blue eye, white splash. not so much for the blue eye/no white splash in a GSD.
anyway, this is pretty quick getting over my head so I'm done.
but if anyone needs to know how to wire up a 3-way light in your Panda kennel, I'm the guy.
and still not convincedl but open,
by Rik on 05 April 2020 - 17:04
purebred A/Can S/l? purebred SV S/L, purebred SV W/L, flyball, dock diver, Czech, purebred GSD rescue?
seriously, some of these lines are separated by 100+ years of breeding. I seriously doubt there is any such thing as "purebred" GSD DNA.
just because someone found a "mutation" on a gene does not mean that gene came from a "pure bred" GSD.
by Sunsilver on 05 April 2020 - 17:04
Ah, okay, Rik, I guess I was thinking more of the Lassie pattern, with the white neck ruff.
If I were to go back to university in my old age, the one thing I'd love to learn more about is genetics! I'd like to be able to read that last paper I linked to, and understand everything they're saying. Maybe I will do that some day - my alma mater used to offer free courses to alumni who where past the age of 65, and it could be they still do!
But first I've got a month of radiation to look forward to...[grumble] And no, between being treated for breast cancer, and not getting out anywhere due to COVID-19, that's not gonna happen anytime soon, unless I can do it online!
Let me try one last explanation. Franka's colouration was caused by a mutation in what's known as the KIT gene. Geneticists not only know what chromosome this gene is located on, they know exactly what it does. In mammals other than German shepherds, it controls white spotting. For some reason, in German shepherds it doesn't cause white spotting. It's there, but it seems to be inactive.
Then, in Franka, a section of that chromosme went missing. There was what genetecists call a deletion. It seems that whatever section of that chromsome was deleted was blocking the KIT gene from being expressed. Unfortunately, parts of the deleted information also controlled vital body processes, such as formation of nerves, and this is why a dog that has 2 copies of the mutated gene dies in utero. If the dog is heterozygous and has one mutated copy of the gene and one normal copy, the normal copy covers for the mutated one, produces normal nerves and brain cells, and the embryo can survive. Scientists aren't guessing at this: they KNOW just exactly what the missing part of the chromosome does, and have observed it in other animals. That was one of the most amazing things they discovered when they were first able to sequence genes and figure out just what their function they had: a particular gene wasn't specific to a particular animal, but would often pop up in different species, sometimes even species that weren't closely related to each other. And it would have almost EXACTLY the same function! So, the science behind this is pretty rock-solid, even if I don't understand it as well as I'd like to.
by Sunsilver on 05 April 2020 - 17:04
what is "pure bred" GSD DNA? purebred A/Can S/l? purebred SV S/L, purebred SV W/L, flyball, dock diver, Czech, purebred GSD rescue? seriously, some of these lines are separated by 100+ years of breeding. I seriously doubt there is any such thing as "purebred" GSD DNA. just because someone found a "mutation" on a gene does not mean that gene came from a "pure bred" GSD.
Rik, want to get the doggies out for a walk, so in a hurry. Suggest you read up about what's involved in genetic testing of dogs to find out what breed they are. I am fairly sure each breed has specific genetic markers they look for to determine the parentage of mixed breeds. I am 90% sure any non-GSD genes would have been spotted during the extensive genetic testing done on Franka and her parents.
To be 100% certain about that...well, that's why I'd like to take that genetics course!
by Rik on 05 April 2020 - 17:04
SS, very sorry to hear that. I went through the radiation and heavy chemo (red devil) in 2016 (and I'm good so far) so I absolutely know the anxiety and fear that comes with that, and absolutely believe in prayer and you are on my list.
and I really want to (well have to now) keep this on a civil level, which I think we have done.
you believe it is true, I believe it is a hoax.
I see no reason we can't discuss it and present our views from both sides.
best to you,
by Hundmutter on 06 April 2020 - 02:04
Rik, WTF are Judges doing giving out Show awards to THAT ???
I thought even AKC required Judges to judge 'to the Standard'.
(Assuming from AKC reg numbers that this is an American Show, not a Canadian one ?)
by Hundmutter on 06 April 2020 - 03:04
Sunny, I'm sorry but I do not understand your comment:
"Suggest you (Rik) read up on genetic testing of dogs to find out what breed they are ..."
I thought that it was fairly common knowledge that these DNA tests (as opposed to proper parental DNA ID testing) are not worth the paper they are printed on, and that people are regularly ripped off by firms offering them ?
To rely on them to support your argument about the genetic mutation cited in Franka's case seems a little perverse.
by Rik on 06 April 2020 - 08:04
hund, it appears this show was a "rare breeds club" not sure what that means but not AKC or CKC. had to get mag glass to read it on the placard.
I have read quite a bit on DNA. here is what AKC has to say:
and here is a direct quote from that article:
"Furthermore, AKC DNA Profiles cannot determine the breed of a dog or if a dog is purebred."
by Hundmutter on 06 April 2020 - 11:04
Oh OK - Like our 'Whites and LongCoats Society' then (their Fun / Companion Shows looking a little bereft since the SV allowed 'coats to be back in 'proper' Showing).
Should they not call themselves a "Rare Colours" Club, though, not a "Rare Breeds" one - or are there people who think white splotches or blue eyes when non standard in a breed = a new breed ? The French Bulldog people need to watch out !
Trouble is, just about anybody (celebs, trainers, dog food manufacturers) can be 'judges' at these things, without knowing the first thing about pedigree pooches - but the general public takes it that "well they're all Dog Shows so what gets put up there MUST be good specimens and breed typical".