Tell me about retained testicle in puppies.

[Houndhill]

[QUOTE=Kyzteke;7851333]
You mean"X-linked" and “autosomal” mean the same thing? I know in several articles they stated “X-linked, autosomal recessive trait” and I quoted it as such. I’m certainly not a geneticist. In this case I’m just parroting what I read.

Is the phrase incorrect?[/QUOTE]

I’m no geneticist either, but as I understand it, a chromosome is either a sex chromosome (X or Y), or it is an “autosomal” chromosome (one of the others not X or Y). It can’t be both, hence they are mutually exclusive.

I read “X-linked recessive” in a couple of these articles, though most stated it wasn’t that simple, that non-genetic factors could affect the expression of genes, etc., and that there may well be different physiological causes of monorchidism/cryptoridsm, and that the mode of inheritance might be different in bilateral vs unilateral cryptorchidism.

To make this horse- related, I did not know that AP Indy was monorchid.

[alto]

@Houndhill;7851529

I’m no geneticist either, but as I understand it, a chromosome is either a sex chromosome (X or Y), or it is an “autosomal” chromosome (one of the others not X or Y). It can’t be both, hence they are mutually exclusive.

I read “X-linked recessive” in a couple of these articles, though most stated it wasn’t that simple, that non-genetic factors could affect the expression of genes, etc., and that there may well be different physiological causes of monorchidism/cryptoridsm, and that the mode of inheritance might be different in bilateral vs unilateral cryptorchidism.

This study was presented at a 2010 conference - it’s an excellent study as all dogs involved were examined by a given vet team (rather than various vets/owners).

X-linked, autosomal recessive trait

indicates that the condition is “X-linked” as in only observed/expressed in one sex (the boys) & is “autosomal recessive” in inheritance, genes involved in expression etc are on the non-sex chromosomes & are recessive … as it’s likely that multiple genes are involved, simple mendelian genetics (that punnett square) do not apply.

(note that it’s been clearly proven that Mendel applied … hmmm … some subjectivity to his data )

[mommy_peanut]

X-linked, autosomal recessive trait is correct. It just means that it’s passed on the X chromosome, but needs both parents to be carriers of(or positive for) that particular trait in order to pass in on to their offspring.

This article breaks in down & explains it well.
http://ghr.nlm.nih.gov/handbook/inheritance/inheritancepatterns

[Horsegal984]

[QUOTE=mommy peanut;7851640]
X-linked, autosomal recessive trait is correct. It just means that it’s passed on the X chromosome, but needs both parents to be carriers of(or positive for) that particular trait in order to pass in on to their offspring.

This article breaks in down & explains it well.
http://ghr.nlm.nih.gov/handbook/inheritance/inheritancepatterns[/QUOTE]

Actually no, to pass on an X linked trait to a male only the mothers status matters. Males are XY, females are XX. So to have a male pup they get one X chromosome from the mother and the Y from the father. The father would either be affected or non carrier, males cannot be carriers for X linked traits.

Think of color blindness for example. I know I am a carrier for it, because it is X linked recessive. My father is colorblind and only has that one X chromosome to pass on while my mother has two. If I have a son, there is a 50/50 chance he will be colorblind. If my husband is colorblind or not, it wouldn’t affect his son because he gives them only a Y chromosome. Now if my husband was colorblind and we had a daughter there is a good chance she will be colorblind as well since I am a carrier and he HAS to give her his affected X chromosome.
Punnett square with Non colorblind male
|X | x

---

X|XX|Xx

---

Y|XY|xY

Punnett square with colorblind male
|X | x

---

x|Xx|xx

---

Y|XY|xY

[D_BaldStockings]

Autosomally transmitted is other than on the sex chromosomes.

Female dogs are unaffected carriers.

Male dogs can be affected at different levels; and there are probably developmental crypts, too.

But if it is a simple dominant then either parent can pass on the gene but males will be affected (so the sire would have been affected).

This is why breeders say the females transmit the gene as most ethical breeders do not use crypt males for breeding and you can’t tell by looking at a female if she is a carrier.

[mommy_peanut]

Horsegal,

Yes that makes sense, except that every vet & geneticist I’ve talked to about crypts, has said both parents need to be carriers for the offspring to be affected.
So now I’m just confused…LOL
I know that the current belief is there is more than one gene that is responsible for causing crypts. Maybe that is were I mixed the info up along the way…

[Horsegal984]

I think the end of Alto’s post above explains the multi-genome link (and also explains how it’s both X linked and autosomal) and why both parents have to be carriers.

The link you posted to explains the basics well, I didn’t read on to see if/how they broke down traits that are multi-genome dependent. Multi genome traits we’re all familiar with are things like hair color and skin tone. It’s what makes the color range so vast, instead of there simply being black (BB) brown (Bb) or blonde (bb). It’s more like black hair (BBNnAacc) auburn (BBNnAAcc) brown (BbNNAaCc) etc.
Cryptorchids are more like hair color, but it’s thought the on/off switch for expression may be on the X chromosome. (At least from what little research I’ve done since this thread popped up)

[D_BaldStockings]

[QUOTE=mommy peanut;7852206]
Horsegal,

Yes that makes sense, except that every vet & geneticist I’ve talked to about crypts, has said both parents need to be carriers for the offspring to be affected.
So now I’m just confused…LOL
I know that the current belief is there is more than one gene that is responsible for causing crypts. Maybe that is were I mixed the info up along the way…[/QUOTE]

If both parents need to be carriers, then you have an autosomal recessive.

If one had a female with both genes, she would still be normal. Then if she was bred to a carrier male, statisticall 1/2 of her male pups would be crypts, 1/2 carriers; while her female pups would be the same except they would not express the trait, being female.
If she was bred to a normal non-carrier male, theoretically none of her pups would show as crypts, though all would be carriers.

Breeding can be an uncertain roll of the dice at times:
you don’t know what you have until those recessive genes meet up with another recessive gene, then oh, c**p!

[alto]

@D_BaldStockings;7852469

If one had a female with both genes, she would still be normal. Then if she was bred to a carrier male, statisticall 1/2 of her male pups would be crypts, 1/2 carriers; while her female pups would be the same except they would not express the trait, being female.
If she was bred to a normal non-carrier male, theoretically none of her pups would show as crypts, though all would be carriers.

This is Mendelian genetics - which some researchers were indicating did NOT apply
(instead there in a complex interplay)

[Kyzteke]

[QUOTE=Houndhill;7851529]

To make this horse- related, I did not know that AP Indy was monorchid.[/QUOTE]

THAT I knew. As an old tracker myself, I can tell you that TB race horse breeders don’t care about much of anything except “how fast can they run?”

They could have 4 balls and it wouldn’t matter if that horse could set track records.

[Houndhill]

[QUOTE=Kyzteke;7853163]
THAT I knew. As an old tracker myself, I can tell you that TB race horse breeders don’t care about much of anything except “how fast can they run?”

They could have 4 balls and it wouldn’t matter if that horse could set track records.:D[/QUOTE]

Was he bred from? Can you register foals JC if the sire is monorchid?

[Ghazzu]

[QUOTE=Kyzteke;7851333]
You mean"X-linked" and “autosomal” mean the same thing? I know in several articles they stated “X-linked, autosomal recessive trait” and I quoted it as such. I’m certainly not a geneticist. In this case I’m just parroting what I read.

Is the phrase incorrect?[/QUOTE]

No; I mean that the definition of autosomal means that the trait in question is not on a sex chromosome, and the definition of x-linked means that the trait in question is on a sex chromosome.

[MsM]

The terminology I was familiar with would have an autosomal trait such as this as “sex-limited” (Only expressed in one sex) rather than “sex-linked” (Carried on sex chromosome so couldn’t be autosomal)

[Ghazzu]

[QUOTE=MsM;7854350]
The terminology I was familiar with would have an autosomal trait such as this as “sex-limited” (Only expressed in one sex) rather than “sex-linked” (Carried on sex chromosome so couldn’t be autosomal)[/QUOTE]

Just so.

[wendy]

undescended testicles isn’t a single-gene, highly penetrant trait- it doesn’t produce the classic 50% of pups etc. you just occasionally see a pup pop up with it. It is, however, a recessive autosomal genetic trait, and if a case appears neither parent should ever be bred again.
Who breeds a less than one year old dog?

[mommy_peanut]

[QUOTE=wendy;7854727]
undescended testicles isn’t a single-gene, highly penetrant trait- it doesn’t produce the classic 50% of pups etc. you just occasionally see a pup pop up with it. It is, however, a recessive autosomal genetic trait, and if a case appears neither parent should ever be bred again.
Who breeds a less than one year old dog?[/QUOTE]

I agree with the first part, but not the second.
There’s no reason to toss the baby out with the bath water.
Just because a breeding produced a crypt puppy, does not mean those dogs should be removed from breeding.
There are many other reasons for a dog being a crypt, besides genetic.
If only one pup out of a litter ends up a crypt, chances are greater it’s NOT due to genetics.
I wouldn’t bred those two particular dogs together again though.

[Kyzteke]

[QUOTE=Houndhill;7854316]
Can you register foals JC if the sire is monorchid?[/QUOTE]

Yep. To the best of my knowledge, the JC does not require any sort of “standard” in terms of conformation or even what show dog people consider “unsound traits” (stuff like bites, testicle placement, odd markings, etc).

That is because TB race horses are “purpose bred.” They are bred to run and if they can do that successfully they win a place at the breeding table once they retire. Mares often don’t even need to have had successful racing careers to be valued broodies.

Although this focus on just one thing has created some problems in the breed, it still remains (IMHO) a more fruitful practice than breeding for an arbitrary “standard” of excellence than is based only on looks.

They just need to have both parents JC registered and to have been conceived via live cover. Nothing else, unless the rules have changed since I was involved in the racing industry.

[Kyzteke]

[QUOTE=wendy;7854727]
undescended testicles isn’t a single-gene, highly penetrant trait- it doesn’t produce the classic 50% of pups etc. you just occasionally see a pup pop up with it. It is, however, a recessive autosomal genetic trait, and if a case appears neither parent should ever be bred again.
Who breeds a less than one year old dog?[/QUOTE]

If you research the history of many breeds, a number of mono-crypts have had a very positive influence.

I recall back when I had Bull Terriers, many breeder mentioned this one stud dog (I believe he was British) who had just a single teste descended. He was one of the top dogs of his breed and an awesome sire.

And truly, in the grand scheme of things, stuff like having just one testicle or a bite that is not perfect or a hair coat that is not “typey”, etc. etc. have nothing to do with the mental or even physical soundness of a dog. These are things people have decided are “bad”, but unless carried to extreme, don’t affect the usability of the animal.

Refusing to breed BOTH the male & female just because one pup has retained testicles makes no sense at all.

In the case of my friend, because of the high % of pups affects, I have no doubt she will not use this stud dog again, although I know she plans to breed the female again at some point.

I know nothing about Shih Tzus, but I know both dogs have had a great deal of success in the show ring…I’m pretty sure the bitch is already finished and the male is still being shown, but I know my friend was going on and on about how fantastic his pedigree was.

So it was a perfect example of how “breeding best to best” turned out to be…ummm, NOT so “best”.

But then again, everything I’ve read stresses that they are not 100% positive it IS genetic. Perhaps the bitch was exposed to some sort of toxin…

[S1969]

[QUOTE=Kyzteke;7854747]
I know nothing about Shih Tzus, but I know both dogs have had a great deal of success in the show ring…I’m pretty sure the bitch is already finished and the male is still being shown, but I know my friend was going on and on about how fantastic his pedigree was.

So it was a perfect example of how “breeding best to best” turned out to be…ummm, NOT so “best”…[/QUOTE]

I wasn’t really going to get into this because I know you’re not the owner, but no, “breeding the best to the best” means age appropriate health clearances are done before breeding. In this case, none of them may have picked up something that would have necessarily have prevented this specific issue (if, in fact, it was genetic) but other issues like luxating patellas, hip and elbow problems (if found in that breed) can’t really be assessed properly before age 2. The fact that the male is “still being shown” means he still has to prove he is even worthy of breeding. (Maybe he is, but what was the big hurry – not even a year, and not finished yet.)

There is always an element of risk in breeding, but I wouldn’t exactly call this an example of great breeding. Maybe a year from now – and maybe the outcome would have been the same, but at least the breeder wouldn’t have people asking why she bred to an unfinished, adolescent male.

[Houndhill]

[QUOTE=S1969;7854795]
I wasn’t really going to get into this because I know you’re not the owner, but no, “breeding the best to the best” means age appropriate health clearances are done before breeding. In this case, none of them may have picked up something that would have necessarily have prevented this specific issue (if, in fact, it was genetic) but other issues like luxating patellas, hip and elbow problems (if found in that breed) can’t really be assessed properly before age 2. The fact that the male is “still being shown” means he still has to prove he is even worthy of breeding. (Maybe he is, but what was the big hurry – not even a year, and not finished yet.)

There is always an element of risk in breeding, but I wouldn’t exactly call this an example of great breeding. Maybe a year from now – and maybe the outcome would have been the same, but at least the breeder wouldn’t have people asking why she bred to an unfinished, adolescent male.[/QUOTE]

It is possible this male is still being shown, not because he has not yet finished his championship (although that is possible, and if so, is not necessarily an indication of his quality, or lack thereof), but perhaps has finished, and is now being shown at the Group/BIS level.

I think we should be careful in making assumptions about the quality of this dog, his health clearances appropriate for his breed, or the wisdom of going forward with him, given the inconclusive nature of the genetic basis for cryptorchidism.

This is a toy breed, they mature more quickly than some other breeds, and perhaps appropriate health testing has occurred, we do not k ow.