Hello there!  I've done a fair amount of research on the genetics of dachshunds, "my breed" (although I am not a breeder, at least yet), but I still have some [randomish] questions, a couple of them concerning brindling.

- I am aware that in dachshunds, brindling must be shown (cannot be carried) in order to appear in offspring.  Is this true of all dog breeds?

- I have seen heavily brindled pit bulls (of various breeds/subbreeds) before.  One very young bitch in particular I've seen in person was simply breathtaking - a gunmetal grey with black stripes.  As far as I am aware and have been told by two dog geneticists, brindling can only show in "red" areas of a dog; for dachshunds, this would include red, cream, tan points, and cream points.  I assume that the particular "pibble" :) I saw was a fawn* with extremely heavy brindling.  Can I also assume that her parents were likely both brindles and that the brindling therefore was heavy on her?  I ask this because in dachshunds, I've noticed it's seems to be fairly easy to figure out what the parents of a dog who is a dapple (merle) look like:  if the dappling is sparce or up to half-covered, the dog probably has no double dapples in its recent history, but if its dappling is heavy, then it probably has one double dapple parent.  (Of course, it could be the case that I'm full of it and have just been lucky with my observations!  Please do correct me if I am wrong.)  If that is the case, can the brindling work the same way [in the breed]?  I wonder, for instance, if a somewhat heavily brindled cream can be produced from two cream brindle parents, perhaps to look something like the pibble I saw.  And further, if that is the case, can the brindling be enhanced over generations (and not just parents->direct offspring) by continuously mating brindle to brindle?

Thank you in advance for any info!

* The term fawn (isabella) in dachshunds refers to a diluted chocolate, which is probably not what I'm referring to with the pibble, but not being familiar with pibble color variety and nomenclature, I'm not sure.

Question for Julie V methinks....she may be along later...

Jo and the Casblaidd Flatcoats

Does this help you?  (Can't remember how to do links, can't be bothered to look ;)!)

http://skyway.usask.ca/~schmutz/dogpatterns.html

For what it's worth, and not claiming to know - going from the merle pattern in my breed, I would guess that the actually brindling/merling patterns are fairly random and not indicated by heaviness of markings on parents.  However, as always, will check back later and be interested to be educated.

M.

An interesting point M about merle and brindle being random.  Although there is undoubtedly some genetic contol, the asymetric patterns do seem to be partly random.  I've see photos of merle ASDs, said to be identical twins, where the patterns were quite different. 

This could be more noticable in merles because the pattern is influenced by the distribution of white markings and this is definitely random to some extent as the distribution of migrating pigment cells during foetal development is not entirely under genetic control.  This has been seen in cloned animals of other species eg black & white Holstein cattle and tabby & white cats.

Julie

Fascinating.  Thanks for the info!

Hi M.  I had seen that page months ago but had somehow forgotten about it when I thought up my current questions.  Thanks for the link!

Yes, you are right about brindle showing only in the red areas as brindle is dark-stripes-on-a-light-background not the other way round.  So if a dog is brindle but also tanpoint, the brindle will only show in the tan areas. But....there is also the case of pseudo brindle which is where a genetically brindle can have either very few stripes, so would appear to be clear red or, have very heavy brindling so appear solid black.

Brindle is the same gene in all breeds as far as I know but of course in breeds that have solid dark colours eg black SBTs, it can be carried without showing.

The amount of striping is controlled by separate genes/modifyers so a line that has heavy striping would be more likely to produce heavy striping.  The way to "improve" brindling would obviously be to select for it but non brindle dogs introduced into the line could well carry the genes for the wrong sort of brindling even though they are not actually brindle.

I don't know if a homozygous brindle (Kbr Kbr) looks any different to a heterozygous (Kbr k). I certainly haven't seen any evidence to suggest this so I would doubt that you could tell if a brindle came from one or both brindle parents.  The double dapple parent prediction doesn't really make sense as each parent passes on only one merle allele to its offspring no matter how many it has itself.

The pibble was probably a very pale fawn (sable Ay).  Couldn't have been chocolate or dilute or it wouldn't have had black stripes.

Julie

"Brindle is the same gene in all breeds as far as I know but of course in breeds that have solid dark colours eg black SBTs, it can be carried without showing."

Alrighty.  I've always heard that, at least in dachshunds, it absolutely must be shown to be passed on.  But I have also heard a couple of breeders swear that their red dogs who have produced brindles before weren't themselves brindles although they "carried for it".  I have wondered since then whether that was a possibility or not - if that happens in other breeds.

"but non brindle dogs introduced into the line could well carry the genes for the wrong sort of brindling even though they are not actually brindle."

Hmm...  I hadn't considered that at all.

"I don't know if a homozygous brindle (Kbr Kbr) looks any different to a heterozygous (Kbr k). I certainly haven't seen any evidence to suggest this so I would doubt that you could tell if a brindle came from one or both brindle parents.  The double dapple parent prediction doesn't really make sense as each parent passes on only one merle allele to its offspring no matter how many it has itself."

I did feel a little stupid asking that.  :)  (I.e., I didn't know if maybe the one merle could affect the other merle, or if it could affect anything else around it in the chromosomes or not.  I figured that was a longshot.)

"The pibble was probably a very pale fawn (sable Ay).  Couldn't have been chocolate or dilute or it wouldn't have had black stripes."

Gotcha.

Thank you so much for your help, Julie!

The other possibility to explain reds carrying brindle is that you have recessive yellow (ee) in the breed.  This is the gene that produces red/gold/yellow in many of the gundog breeds and  does occur in many other breeds.  Genotype ee Kbr_ would be a solid red, mated to E_ would produce brindle.

Julie

Thanks once again, Julie.

i didnt think brindle dacshund existed!

They do.  =)  Any dachshund that has red, cream, or tan on it (all varieties of red, basically) can show brindling.

Here are some very fine longhair specimens:

http://www.weatherlysdachshunds.com/creams.html
http://www.garlindox.com/cream.html

And here are nice smooth ones with brindling in points and in piebald spots:

http://www.ka-kas-royal-doxies.com/www/Scrappi.htm
http://www.ka-kas-royal-doxies.com/www/Tricksi.htm

they are sooooooooo cute .you learn something new every day! thanks for the links.
regards sarah x

Sorry I'm a little slow in responding!  I wanted to say, you're welcome, and I seem to learn something new every day too!  =)