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by petowner on 15 February 2010 - 16:02
I agree with you Hodie. Good post. Simon.
by AmbiiGSD on 15 February 2010 - 17:02
I would be interested in reading it if you could, thanks Hodie.
My point is that by eliminating one defective gene, what other genes might we be eliminating that are somehow tied to it, that would be beneficial.
Has for instance any research been done into the longivity and health of littermates of dwarf pups? Do they seem to live long healthy lives? or do they have health issues themselves. Do carriers have health issues? or do they appear to not succumb to other scourges of our breed?
My point is that by eliminating one defective gene, what other genes might we be eliminating that are somehow tied to it, that would be beneficial.
Has for instance any research been done into the longivity and health of littermates of dwarf pups? Do they seem to live long healthy lives? or do they have health issues themselves. Do carriers have health issues? or do they appear to not succumb to other scourges of our breed?
by hodie on 15 February 2010 - 17:02
AmbiiGSD,
I think there is enough anecdotal evidence to say that litter mates not afflicted with pituitary dwarfism go on to lead relatively normal, health lives. Of course, we all end up with some affliction, and I am including humans. I am always surprised when people do not think about the issue broadly. For a fact, there is no perfect human, without some sort of ills showing up sooner or later. Some have it earlier than others, but, short of injury or acute illness, all things are genetic, including the timing of the length of our lives to a large extent. It is no different with dogs.
Knowing a specific gene has a mutation that causes such a terrible problem as dwarfism is a good thing. Someday there will be therapy to fix the problem. There is already research done on how to treat such pups who are born with the condition.
I understand your concern, but recognizing carrier states for any type of genetic defect, be it in human beings or animals, is not eliminating any gene. It is hopefully preventing the coming together of mates who could each pass on the defect to offspring, at least in the case of autosomal recessive genes. So no genes are eliminated, and, indeed, it is still possible for a carrier to pass on his or her defective gene to the progeny. But, again, if that progeny is known to carry the defective gene, and is never mated to a carrier of the defective gene, no genetic defect related to this defective gene will be present in progeny, with the exception of potentially carrying the defect. Even if two are mated who carry the defect, the statistical odds in the first generation are about 25% of the offspring will be born with carrying two copies of the bad gene, and, in this situation, born as dwarfs. But, the presence of one defective gene in this case does not code for the expression of the defect if only a single defective copy of the gene is present. Remember, we inherit a copy of every gene we have from our parents, one copy from the mother, one from the father. So for an autosomal recessive trait to show up in the first generation, both parents have to have a defective copy of the gene that is passed on to one of the progeny. That happens in about 25% of the time. But in the next generation, if care is not taken to avoid the defect when mating, the odds go up to 50%.
I am asking a question here and not trying to offend anyone. Do you all understand what an autosomal recessive gene is? Do you know what a Punnett Square is? Do you understand the terms allele or dominance or recessive? If not, I would be glad to explain it. That would also help to understand that siblings may be born absolutely "normal", however we want to define normal.
I think there is enough anecdotal evidence to say that litter mates not afflicted with pituitary dwarfism go on to lead relatively normal, health lives. Of course, we all end up with some affliction, and I am including humans. I am always surprised when people do not think about the issue broadly. For a fact, there is no perfect human, without some sort of ills showing up sooner or later. Some have it earlier than others, but, short of injury or acute illness, all things are genetic, including the timing of the length of our lives to a large extent. It is no different with dogs.
Knowing a specific gene has a mutation that causes such a terrible problem as dwarfism is a good thing. Someday there will be therapy to fix the problem. There is already research done on how to treat such pups who are born with the condition.
I understand your concern, but recognizing carrier states for any type of genetic defect, be it in human beings or animals, is not eliminating any gene. It is hopefully preventing the coming together of mates who could each pass on the defect to offspring, at least in the case of autosomal recessive genes. So no genes are eliminated, and, indeed, it is still possible for a carrier to pass on his or her defective gene to the progeny. But, again, if that progeny is known to carry the defective gene, and is never mated to a carrier of the defective gene, no genetic defect related to this defective gene will be present in progeny, with the exception of potentially carrying the defect. Even if two are mated who carry the defect, the statistical odds in the first generation are about 25% of the offspring will be born with carrying two copies of the bad gene, and, in this situation, born as dwarfs. But, the presence of one defective gene in this case does not code for the expression of the defect if only a single defective copy of the gene is present. Remember, we inherit a copy of every gene we have from our parents, one copy from the mother, one from the father. So for an autosomal recessive trait to show up in the first generation, both parents have to have a defective copy of the gene that is passed on to one of the progeny. That happens in about 25% of the time. But in the next generation, if care is not taken to avoid the defect when mating, the odds go up to 50%.
I am asking a question here and not trying to offend anyone. Do you all understand what an autosomal recessive gene is? Do you know what a Punnett Square is? Do you understand the terms allele or dominance or recessive? If not, I would be glad to explain it. That would also help to understand that siblings may be born absolutely "normal", however we want to define normal.
by AmbiiGSD on 15 February 2010 - 18:02
sent you a PM Hodie...you may find it interesting.
by missbeeb on 15 February 2010 - 18:02
Hodie, I understand most of the basics (I think) having Malcolm Willis' book on genetics, but I would be very glad of a "lesson" here, as you seem to simplify things sufficiently for my feeble brain to understand. I don't know what a Punnett Square is... I'm ok with the others you mention.
Many thanks in anticipation...
Babs
by AmbiiGSD on 15 February 2010 - 18:02
Missbeeb
Have a read here, but pay particular attention to the bottom of the article.
And remember that genetic theory is just that, theory.
en.wikipedia.org/wiki/Punnett_square
Have a read here, but pay particular attention to the bottom of the article.
And remember that genetic theory is just that, theory.
en.wikipedia.org/wiki/Punnett_square
by jayne241 on 15 February 2010 - 18:02
"And remember that genetic theory is just that, theory."
Sorry, this is one of my little pet peeves... just because it says "theory" does NOT mean it is an unproven *hypothesis*.
Einstein's Theory of General Relativity is a more accurate description of gravity than Newton's "Law" of Gravity. It's just that back then, we were more apt to call things "Laws" instead of "Theories". When scientists call something a "theory" they don't mean it is just a guess. A guess would be a hypothesis.
Don't discredit something simply because it has the word "theory".
Sorry, this is one of my little pet peeves... just because it says "theory" does NOT mean it is an unproven *hypothesis*.
Einstein's Theory of General Relativity is a more accurate description of gravity than Newton's "Law" of Gravity. It's just that back then, we were more apt to call things "Laws" instead of "Theories". When scientists call something a "theory" they don't mean it is just a guess. A guess would be a hypothesis.
Don't discredit something simply because it has the word "theory".
by AmbiiGSD on 15 February 2010 - 18:02
Genetics are based on probability... probability is a theory....
That's a whole different debate... and a whole different forum. ;)
That's a whole different debate... and a whole different forum. ;)
by missbeeb on 15 February 2010 - 19:02
Thanks for that, AmbiGSD.
The delay in replying is due to my having to read the info several times to get an understanding... lol. I don't think I'm particularly thick,
but I have a real mental block with anything that seems even remotely mathematical. Not my "bag" at school and no improvement since! 
The delay in replying is due to my having to read the info several times to get an understanding... lol. I don't think I'm particularly thick,
but I have a real mental block with anything that seems even remotely mathematical. Not my "bag" at school and no improvement since! by pencil on 15 February 2010 - 19:02
ambi gsd:
Having tested your reasoning i am pleased to say you are correct.
Cos the THEORY is that if the Breeders in question admitted it and informed us, it would help.
but the PROBABILITY of that happening is NIL.
Having tested your reasoning i am pleased to say you are correct.
Cos the THEORY is that if the Breeders in question admitted it and informed us, it would help.
but the PROBABILITY of that happening is NIL.
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