Panama
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Well stated Silent!
White dobermans
- Thread starter Zeus19742008
- Start date
Well stated Silent!
nc_dobemom
Novitiate
What do you mean by this?
Albinism is a recessive gene that is passed from both parents. How can it just viola! you are an albino without both parents having the gene? That makes no sense to me and I've never heard of it happening.
http://www.answers.com/mutation
mutation
n.
mutation
n.
- The act or process of being altered or changed.
- An alteration or change, as in nature, form, or quality.
- Genetics.
- A change of the DNA sequence within a gene or chromosome of an organism resulting in the creation of a new character or trait not found in the parental type.
- The process by which such a change occurs in a chromosome, either through an alteration in the nucleotide sequence of the DNA coding for a gene or through a change in the physical arrangement of a chromosome.
- A mutant.
- Linguistics. The change that is caused in a sound by its assimilation to another sound, such as umlaut.
DoberDon~ My carpenter's name was Byron Kibby. His band was, I think, but don't quote me on this, Byron and the Blue Notes. I know what you mean about the voice going after an all night session. Back in the day I dated Bobby Wayne Lofits who sang country. He managed to put out two albums before he passed in '90. Some nights he would loose his voice by the time the session was over. He played piano as well. He had an incredible voice range and could do Bobby Mc ghee(?) just like Janis; screaming and all.
deladobies
Member
Come on now...that was a little uncalled for dont you think.
We dont always have to agree, but we do need to respect one another...
No one has to post a response on every thread, if you dont agree, say so but please dont insult people on the forum... Im sure we all know how horrible that feels, dont do it to someone else!
We dont always have to agree, but we do need to respect one another...
No one has to post a response on every thread, if you dont agree, say so but please dont insult people on the forum... Im sure we all know how horrible that feels, dont do it to someone else!
oor horse....Pretty Paws
New Member
Okay, I know I am new but I have to chime in.
I do not know very much about canine genetics beyond the basics such as canines have 39 chromosomal pairs, one pair sexual and the rest are autosomal, etc.
I do know more than the average person about how genetics operate in general with more specific knowledge of how they operate in humans. Although I am no expert by any means. I do have the ability to understand the findings of those experts.
I have to disagree with the inference of this definition of a mutation:
originally written by Silent
The definition is technically correct, but is misleading. It does not tell you how any one mutation behaves, how it is expressed, or inherited. It does not differentiate between genotype and phenotype.
For those who are unfamiliar with the terms, the phenotype is all of the genes that an organism possesses in their genetic make-up. Half of those genes are supplied by each of their parent donors. The genotype is the genes that are being expressed in that organism. They ar the active genes. The rest lay dormant but can still be passed onto the organisms offspring. A mutation can occur in the genotype of an organism that was not in the genotype of it's parents, but not be expressed in the organism's phenotype.
The mutation of albinism only occurs in a single gene, not a single gene pairing. It is a recessive gene. It takes two recessives for the organism to express the trait. Since when the mutation of albinism occurs it only occurs in one of the genes in the pairing it is not expressed phenotypically by the organism in which the mutation originally occurs. The recessive gene of albinism can be passed on from parent to offspring genotypically throughout the generations without ever being expressed. It remains hidden in the gene pool until a carrier reproduces with another carrier and both by chance donate the recessive to one of thier offspring.
In order for an organism to express (be affected by) albinism they have to inherit the recessive mutation from both parents.
In the case of the white doberman Padula's Queen of Sheba, she may have been the first recorded white doberman but both of her parents had to already possess the mutated gene. There is no way to determine how far back in each of her parent's family lines the mutation extends, but both family lines have to contain the mutation.
vWD is a similar mutation in how in how it is transmitted and expressed.
I am in no way claiming whether or not I know the white dobe to be an albino. I don't. It has not been proven one way or another. I will wait for the experts to decide. The only thing the experts can tell us is what it is not. It is not the more debilitating form of Tyrosinase Negative Albinism.
In my opinion, a mutation is a mutation. Some mutations affect the organism more severly than others. Every genome has them and the doberman genome is not excluded from that fact.
Like vWD the albino mutation is carried recessively throughout generations without being expressed. Careful breeding of carriers to clears can manage the mutation without severely limiting the doberman gene pool.
Lovers of the breed get too emotionally invested sometimes to think of the situation rationally. The z-list should be used to determine which dogs *may* be carriers. This is the best we can do because we do not currently have a test to determine which dogs are definitively carriers like we do with vWD. Thank God, because vWD is a much more debilitating mutation.
However, using the z-list to eliminate all dogs from breeding that *may* carry a gene that inconclusively is the genetic mutation of albinism no matter how many positive traits they carry with them would have the same effect as eliminating vWD from the doberman's genetic pool.
To truly eliminate the white doberman (under the assumption that is is caused by albinism), you would have to spay/neuter every dobe that has a single shared ancestor of Padula's Queen of Sheba, no matter how far back in the lines that ancestor is.
Albinism, like every mutation, is a spontaneous albeit extremely rare occurrence. To eliminate it from the doberman's gene pool you would have to do the same if it ever occurs again.
All mutations occur more frequently the more the gene pool is limited. The gene pool is limited in dobermans by selective breeding to maintain the standard. It is just a necessary evil. Line breeding (or inbreeding) is used to lock in exemplary traits. This type of breeding locks in these exemplary traits by reducing the number of traits that can be selected from (as both parents carry the same copies of the gene) to hand down to offspring, again reducing the gene pool. It may be useful in maintaining the breed type, but it also exposes recessive traits that may be undesirable and hidden like the mutations of vWD and albinism.
Further reducing the gene pool by removing from breeding every family line that may contain the mutation once it appears would only exacerbate the problem, not solve it. In essence by removing the mutation from the gene pool you increase the odds of it occuring again. If you continue to try to remove these mutations by further reducing the gene pool then other, likely more debilitating mutations than either vWD or albinism, will occur. This is known genetically as "bottlenecking". Continuing on this trend reduces the number of "standard" to choose from generation after generation until there is no choice but to inbreed until the breed is gone.
With careful management, not elimination, of undesirable traits selective breeding can produce both excellent representations of the breed and keep them around long enough for future generations to enjoy them.
I am not suggesting anyone should embrace the white doberman, nor am I suggesting that anyone should or should not breed for whites. I do not know if it is the genetic mutation of albinism.
I am highly dubious of the wisdom in spaying/neutering all z-factored dobermans out of fear of producing a white, especially when the dog is merely a possible carrier. It has me baffled as logically vWD is a more dangerous mutation and does not engender the same response.
I do not know very much about canine genetics beyond the basics such as canines have 39 chromosomal pairs, one pair sexual and the rest are autosomal, etc.
I do know more than the average person about how genetics operate in general with more specific knowledge of how they operate in humans. Although I am no expert by any means. I do have the ability to understand the findings of those experts.
I have to disagree with the inference of this definition of a mutation:
originally written by Silent
The definition is technically correct, but is misleading. It does not tell you how any one mutation behaves, how it is expressed, or inherited. It does not differentiate between genotype and phenotype.
For those who are unfamiliar with the terms, the phenotype is all of the genes that an organism possesses in their genetic make-up. Half of those genes are supplied by each of their parent donors. The genotype is the genes that are being expressed in that organism. They ar the active genes. The rest lay dormant but can still be passed onto the organisms offspring. A mutation can occur in the genotype of an organism that was not in the genotype of it's parents, but not be expressed in the organism's phenotype.
The mutation of albinism only occurs in a single gene, not a single gene pairing. It is a recessive gene. It takes two recessives for the organism to express the trait. Since when the mutation of albinism occurs it only occurs in one of the genes in the pairing it is not expressed phenotypically by the organism in which the mutation originally occurs. The recessive gene of albinism can be passed on from parent to offspring genotypically throughout the generations without ever being expressed. It remains hidden in the gene pool until a carrier reproduces with another carrier and both by chance donate the recessive to one of thier offspring.
In order for an organism to express (be affected by) albinism they have to inherit the recessive mutation from both parents.
In the case of the white doberman Padula's Queen of Sheba, she may have been the first recorded white doberman but both of her parents had to already possess the mutated gene. There is no way to determine how far back in each of her parent's family lines the mutation extends, but both family lines have to contain the mutation.
vWD is a similar mutation in how in how it is transmitted and expressed.
I am in no way claiming whether or not I know the white dobe to be an albino. I don't. It has not been proven one way or another. I will wait for the experts to decide. The only thing the experts can tell us is what it is not. It is not the more debilitating form of Tyrosinase Negative Albinism.
In my opinion, a mutation is a mutation. Some mutations affect the organism more severly than others. Every genome has them and the doberman genome is not excluded from that fact.
Like vWD the albino mutation is carried recessively throughout generations without being expressed. Careful breeding of carriers to clears can manage the mutation without severely limiting the doberman gene pool.
Lovers of the breed get too emotionally invested sometimes to think of the situation rationally. The z-list should be used to determine which dogs *may* be carriers. This is the best we can do because we do not currently have a test to determine which dogs are definitively carriers like we do with vWD. Thank God, because vWD is a much more debilitating mutation.
However, using the z-list to eliminate all dogs from breeding that *may* carry a gene that inconclusively is the genetic mutation of albinism no matter how many positive traits they carry with them would have the same effect as eliminating vWD from the doberman's genetic pool.
To truly eliminate the white doberman (under the assumption that is is caused by albinism), you would have to spay/neuter every dobe that has a single shared ancestor of Padula's Queen of Sheba, no matter how far back in the lines that ancestor is.
Albinism, like every mutation, is a spontaneous albeit extremely rare occurrence. To eliminate it from the doberman's gene pool you would have to do the same if it ever occurs again.
All mutations occur more frequently the more the gene pool is limited. The gene pool is limited in dobermans by selective breeding to maintain the standard. It is just a necessary evil. Line breeding (or inbreeding) is used to lock in exemplary traits. This type of breeding locks in these exemplary traits by reducing the number of traits that can be selected from (as both parents carry the same copies of the gene) to hand down to offspring, again reducing the gene pool. It may be useful in maintaining the breed type, but it also exposes recessive traits that may be undesirable and hidden like the mutations of vWD and albinism.
Further reducing the gene pool by removing from breeding every family line that may contain the mutation once it appears would only exacerbate the problem, not solve it. In essence by removing the mutation from the gene pool you increase the odds of it occuring again. If you continue to try to remove these mutations by further reducing the gene pool then other, likely more debilitating mutations than either vWD or albinism, will occur. This is known genetically as "bottlenecking". Continuing on this trend reduces the number of "standard" to choose from generation after generation until there is no choice but to inbreed until the breed is gone.
With careful management, not elimination, of undesirable traits selective breeding can produce both excellent representations of the breed and keep them around long enough for future generations to enjoy them.
I am not suggesting anyone should embrace the white doberman, nor am I suggesting that anyone should or should not breed for whites. I do not know if it is the genetic mutation of albinism.
I am highly dubious of the wisdom in spaying/neutering all z-factored dobermans out of fear of producing a white, especially when the dog is merely a possible carrier. It has me baffled as logically vWD is a more dangerous mutation and does not engender the same response.
Good post Pretty Paws. That is the best, most common sense filled, description of the Z factored doberman I have heard on here to date. To eliminate one while breeding to include another trait/carrier/gene has never made any logical sense to me. When they develop an accurate test for albinism those promoting opration white out may have a leg to stand on. Until then those arguing for the spay and neuter of all Z factored doberman aren't doing the breed any favors. That's just my thinking.
Pretty Paws
New Member
I know I tried to fix it but it wouldn't let me edit after 10-mins. I am horrible at proofreading. lol
Hi Pretty Paws;
Thanks for the explanation.Does that mean that my example of siamese twins not having siamese twin forefathers isn't applicable because that mutated gene is not recessive? Forgive my ignorance I'm just an electrician who took landscaping for my high school science credit!!Also it was my understanding that there was no controversy whether or not whites were albino? I've read that altho their eyes appear blue they are in fact clear and they are true albinos?
I agree wholeheartedly that all breeding should be to improve health and longevity,with priority to the worst problems,not for a certain"look"
Thanks for the explanation.Does that mean that my example of siamese twins not having siamese twin forefathers isn't applicable because that mutated gene is not recessive? Forgive my ignorance I'm just an electrician who took landscaping for my high school science credit!!Also it was my understanding that there was no controversy whether or not whites were albino? I've read that altho their eyes appear blue they are in fact clear and they are true albinos?
I agree wholeheartedly that all breeding should be to improve health and longevity,with priority to the worst problems,not for a certain"look"
Pretty Paws
New Member
Hi DoberDon!
I am only a biology teacher, no fancy job here either. LOL.
Conjoined twins is caused by a defect in the process of monozygotic twinning, not by genetics. Identical twins are when the one fetilized egg splits into two babies. This type of twinning is chance occurence and not inheritable. It is also not a mutation. It is a natural occurence. Since conjoined twins can only occur in identical twins and the chance of having identical twins is random and not genetic in nature then conjoined twins is a birth defect and not a genetic one.
It can be confusing because fraternal twins (two babies formed from two separate egg/sperm and therefore not identical) occurs when the mother is genetically predisposed to release an egg from both ovaries simultaneously. Most women only release an egg from one ovary at a time alternatively each month.
I have not read your example of siamese twins, so I do not know if it is applicable, but since albinism is a genetic mutation (which is inheritable) and not a birth defect (which is not inheritable)it probably isn't. I hope that helps.
As far as to whether or not the white dobe is a *true* albino as far as I know no one knows for sure. There are four types of albinism that we are aware of. The type of albinism that may be the cause of the white doberman is believed to be located in the P sequence of genes on the "C" gene.
The "C" locus is called the albino gene because we know the Tyrosinase Negative Albino gene is also located on the "C" locus. The "C" locus contains the C-series of genes which is dominant and means full color will be expressed, the C-ch series which removes phaeolmelanin (yellow) pigment, the C-e series or extreme dilution (does not cause dilutes, that is a separate gene locus entirely), the C-p series which retains very slight tyrosinase activity and therefore some pigment, and the c series (lower case) which results in albinism of the type that has no pigment (what we classically think of when we hear the term albino).
The C-p series is what we call Ty-Pos Albinos and the c series are Ty-Neg albinos. The rest of the series of genes (at least in canines) on the "C" locus are not considered to be a form of albinism. Cats also have the C-h series which is considered a form of albinism and causes the points on Siamese and Himalayan cats. In some breeds of cats (rabbits, ferrets, guinea pigs, etc) this form of albinism is controlled and the cats are bred for it.
The "C" locus does not decide color, it decides how that color is expressed. The other series of genes on the "C" locus are not a mutation. They are part of the canine genome. However if the mutation of albinism (the deletion of color by either drastically reducing or eliminating the chemical Tyrosinase) is going to occur that is where it occurs.
We simply do not know enough about Ty-Pos Albinism, which is the type of albinism that does express some color, in dogs to say whether or not the white doberman is caused by that type of albinism. All we can say is that the white doberman does produce some Tyrosinase. We have no way of testing to see if the color is caused by the C-p series or some other series (not albino) on the "C" locus. We do know that it is not caused by the c-series which is the deletion of all color and the absence of Tyrosinase.
I see no reason to debate the unknown. Some people will believe they are Ty-Pos Albinos and some will say they are not. There is strong circumstantial evidence to support both. I don't know if they are Ty-Pos Albinos or not.
I am only a biology teacher, no fancy job here either. LOL.
Conjoined twins is caused by a defect in the process of monozygotic twinning, not by genetics. Identical twins are when the one fetilized egg splits into two babies. This type of twinning is chance occurence and not inheritable. It is also not a mutation. It is a natural occurence. Since conjoined twins can only occur in identical twins and the chance of having identical twins is random and not genetic in nature then conjoined twins is a birth defect and not a genetic one.
It can be confusing because fraternal twins (two babies formed from two separate egg/sperm and therefore not identical) occurs when the mother is genetically predisposed to release an egg from both ovaries simultaneously. Most women only release an egg from one ovary at a time alternatively each month.
I have not read your example of siamese twins, so I do not know if it is applicable, but since albinism is a genetic mutation (which is inheritable) and not a birth defect (which is not inheritable)it probably isn't. I hope that helps.
As far as to whether or not the white dobe is a *true* albino as far as I know no one knows for sure. There are four types of albinism that we are aware of. The type of albinism that may be the cause of the white doberman is believed to be located in the P sequence of genes on the "C" gene.
The "C" locus is called the albino gene because we know the Tyrosinase Negative Albino gene is also located on the "C" locus. The "C" locus contains the C-series of genes which is dominant and means full color will be expressed, the C-ch series which removes phaeolmelanin (yellow) pigment, the C-e series or extreme dilution (does not cause dilutes, that is a separate gene locus entirely), the C-p series which retains very slight tyrosinase activity and therefore some pigment, and the c series (lower case) which results in albinism of the type that has no pigment (what we classically think of when we hear the term albino).
The C-p series is what we call Ty-Pos Albinos and the c series are Ty-Neg albinos. The rest of the series of genes (at least in canines) on the "C" locus are not considered to be a form of albinism. Cats also have the C-h series which is considered a form of albinism and causes the points on Siamese and Himalayan cats. In some breeds of cats (rabbits, ferrets, guinea pigs, etc) this form of albinism is controlled and the cats are bred for it.
The "C" locus does not decide color, it decides how that color is expressed. The other series of genes on the "C" locus are not a mutation. They are part of the canine genome. However if the mutation of albinism (the deletion of color by either drastically reducing or eliminating the chemical Tyrosinase) is going to occur that is where it occurs.
We simply do not know enough about Ty-Pos Albinism, which is the type of albinism that does express some color, in dogs to say whether or not the white doberman is caused by that type of albinism. All we can say is that the white doberman does produce some Tyrosinase. We have no way of testing to see if the color is caused by the C-p series or some other series (not albino) on the "C" locus. We do know that it is not caused by the c-series which is the deletion of all color and the absence of Tyrosinase.
I see no reason to debate the unknown. Some people will believe they are Ty-Pos Albinos and some will say they are not. There is strong circumstantial evidence to support both. I don't know if they are Ty-Pos Albinos or not.
If it were a reccessive carried by dogs prior to the ones designated as z, why have no more shown up? There is a reward offered for any albino that is not from those dogs...that as far as I can find has never been claimed by anyone.
http://whitedobes.doberinfo.com/
Facts About Albino Dobermans
Ione L. Smith, DVM
I have never given my personal opinion on albinos or whether they should be fixed only presented facts as I have found them. I do have a fairly good grasp of genetics.
http://whitedobes.doberinfo.com/
Facts About Albino Dobermans
Ione L. Smith, DVM
I have never given my personal opinion on albinos or whether they should be fixed only presented facts as I have found them. I do have a fairly good grasp of genetics.
Pretty Paws
New Member
That is a good question Silent. I don't know why one hasn't shown up.
I can only speculate:
1) No one has inbred to the degree Sheba was inbred and the albino gene is just lying dormant.
2) No one is interested in a $200 reward, $20,000 maybe
3) Most people, like I did, just thought they bought a mismarked fawn
4) The breeder doesn't want to make public that thier lines are z-tainted and quietly either placed them or euthanized them.
5) the gene hasn't shown up because they are not albino and there is another cause
I can only speculate:
1) No one has inbred to the degree Sheba was inbred and the albino gene is just lying dormant.
2) No one is interested in a $200 reward, $20,000 maybe
3) Most people, like I did, just thought they bought a mismarked fawn
4) The breeder doesn't want to make public that thier lines are z-tainted and quietly either placed them or euthanized them.
5) the gene hasn't shown up because they are not albino and there is another cause
nc_dobemom
Novitiate
I agree with DieKrazy here.....:deadhorse: The white/white factored debate will live in infamy as one of the most heated debates of the Doberman breed.
Agreeing to disagree is the only answer to this. I think this thread should be locked because it is starting to get monotonous.
And Panama I KNOW what validation means FYI.
Agreeing to disagree is the only answer to this. I think this thread should be locked because it is starting to get monotonous.
And Panama I KNOW what validation means FYI.
