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Explanation of Motley and Striped

Serpwidgets
05-21-2002, 10:17 PM
Since this has been a hot topic lately, I thought I'd explain the whole thing and clear up all the confusion.

Grab a deck of cards (or two if you have them) and get the 2s and 9s so you can play along with the illustration. :) Seriously.

Let's say cornsnake genes are playing cards. You have slots for Ace through King. We'll say spades is dominant, and the red "mutant" cards are "recessive" to the black cards.

First example, in 'slot 2' we have amelanism, the Two of Hearts. We also have it's Normal, non-amel counterpart, the Two of Spades.

Every cornsnake inherits a pair of deuces, one from each parent, and each card can be either the two of spades or the two of hearts. (the different twos are what are called "alleles" because they are different but both occupy the same corresponding slot or "locus")

Knowing the basics of inheritance, you know that since the two of hearts is recessive, the only way amelanism will be expressed is if a two of hearts is inherited from each parent. (If not, then a two of spades is going to be present, and it will override the other card) With me so far?

Now, you should also know that an animal that has the Two of Spades and the Two of Hearts is "heterozygous" because the pair of twos it has are different from each other.

It is important to understand that the definition of het is strictly: "the cards of the same number are of different suits" no matter what effect it might have on the animal's appearance!

Ok, let's move on to Motley/Striped. Motley and striped both occupy slot 9. So, unlike every other known cornsnake trait, there are three different cards here:
- 9 of Spades (the dominant wild type allele)
- 9 of Hearts (the Motley allele)
- 9 of Diamonds (the Striped allele)

A "Striped" corn has 2 9s of Diamonds.
A "Motley" corn has 2 9s of Hearts.
A "Striped Motley" has a 9 of Hearts AND a 9 of Diamonds.

A "normal het for striped" has a 9 of Spades and a 9 of Diamonds.
A "normal het for motley" has a 9 of Spades and a 9 of Hearts.
A "normal, not het" has both 9s of Spades.

Reading test: is a "Striped Motley" a Het? ;-)

Ok, so now that we've established that a striped motley is in fact heterozygous, we can move forward...

The surest way to get a "Striped Motley" is to breed a striped corn (pair of 9 of diamonds) to a motley (pair of 9 of hearts) corn. The offspring will all inherit a 9 of diamonds and a 9 of hearts and be what are called "striped motleys."

Remember, these are heterozygous. If you breed two of them together, you will get a result of 100% non-normally-patterned offspring. (25% striped, 25% motley, 50% het Striped/Motley)

I think I've rambled far enough on this, and you can use your playing cards to see the rest of the possibilities. The main point is that there are 3 alleles, so the usual "formulas" don't apply here.

Clint Boyer
05-21-2002, 11:03 PM
That all sounds very clear, theoretically.

According to that theory, no 'normal' corn could be het striped and motley. If it is not displaying a pattern anomoly and one parent was striped-motley then it could only have either a striped OR motley gene from the mutated parent (and you wouldn't know which). Correct?

How do you determine if a Snake is Motely-Striped phenotypically?
I have seen a wide variety of Motley type striped animals. Are they Motley-Striped if they have long abberant stripes?
Can you tell by looking at them if they are Motley-Striped? If not then the only way to call them that would be to know the exact lineage of the animal and they might look identical to an odd Motley with striping.

So, Motley-Striped genotypically is pretty easy to lay out with cards in an understandable fasion.

Phenotypically is a different story. Is anyone up to stepping up to the plate to define a Motley-Stripe by sight?

Hmmm...

P.S. Great job Serpwidgets!

Hurley
05-21-2002, 11:21 PM
You know, this doesn't work out so well with my 'Go Fish' deck.

LOL, great example and explanation Serp! Helps clear up the 'numbers on paper' aspect of things.

Good point Clint, what exactly do you call some of these inbetweener stripey motleyish snakes? Are they homo stripe with variations? Are they homo motleys with variations? Are they motley stripes? Is my S.O.S. marked motley a motley pure and simple? Is he a motley stripe? Without trials, I guess I won't know.

What a wonderful world of morphs!

:p :D

pdrau
05-21-2002, 11:48 PM
Would it be correct to say that if a corn displays homozygous striped and motley traits that it is het for those traits as well?

Thanks for the detailed example Serp. Very helpful and explains how I thought it worked, but was unable to convey.

Peter

Clint Boyer
05-22-2002, 11:57 AM
It can not display both stripe and motley genes and be homozygous for either. If it is showing both traits then it has a motley gene and a stripe gene.

When both genes are the same it's homozygous.

When the 2 genes are different it is heterozygous, regaurdless of what it looks like.

When we use the terms het and homo with simple recessive genes, we know what the snake will look like.

You can not use those terms when dealing with co-dominant genes and expect the same types of results.

pdrau
05-22-2002, 12:41 PM
By display I mean that the snake outwardly shows that it is striped motley.

Peter

Clint Boyer
05-22-2002, 02:55 PM
homozygous does not explain how the snake looks.

Yes, display means how it looks. If a snake is homo for Motley then it has two Motley genes. If it is homo Stripe, then it has two Stripe genes. If it is a true Motley and Stripe (has one motley gene and one stripe gene) then it is actually het for both Motley and stripe but still looks like a Moltey-Stripe.

Darin Chappell
05-22-2002, 03:40 PM
Ok,

So would I be correct in saying that an animal that is motley-striped is one that has "co-recessive" genes at that locus? They really wouldn't be co-dominant would they? If they are both recessive to the natural trait, and the animal is actually het for both motley and stripe, isn't co-recessive a better explanation?

Thanks for the genetics S_T_R_E_T_C_H!!

Darin

Serpwidgets
05-22-2002, 11:49 PM
Originally posted by Darin Chappell
So would I be correct in saying that an animal that is motley-striped is one that has "co-recessive" genes at that locus? They really wouldn't be co-dominant would they? If they are both recessive to the natural trait, and the animal is actually het for both motley and stripe, isn't co-recessive a better explanation?Recessive means it is NOT expressed in the heterozygous state. Dominant means it IS expressed in the heterozygous state, as is the case in motley/Striped.

As you can see, "co-recessive" would imply that they are only expressed when homozygous, which isn't true. :)

Darin Chappell
05-23-2002, 11:49 AM
Gotcha!

Thanks,

Darin

Susan
05-26-2002, 11:30 PM
I don't know what originally started this thread, but I would like to throw a curve into it. I totally agree with serpwidgets genetic explanation of Motley, Striped, and Motley-Striped. However, phenotypically (i.e. how the snake looks) does not always agree with the genetics when dealing with the heterozygous Motley-Stripe. I've only been breeding these morphs for 3 years and have only 3 adult breeders with these morphs. My one female is phenotypically stripe, and I am assuming genotypically homozygous stripe. One male is phenotypically pure motley, no hint of a stripe anywhere, but is het for stripe (the breeder told me he was). Their offspring have been phenotypically "pure" motley, "pure" stripe, and what I call Motley-Stripe, showing both patterns (stripes are present but connect occasionally and/or show the "start" of a connection across the back). My second male is also a phenotypical motley, and I assume homozygous as well. This year is the first time I bred him to my female, and all but 2 of the offspring look almost "identical"...head half looks motley, tail half looks striped with the occasional "start" of connections. One hatchling looks almost "pure" motley and one looks almost "pure" stripe, but does have a few of those partial "starts" of a connection. I have no hesitation in calling all of these hatchlings Motley-Striped.
The curve comes in with my first adult male motley and his offspring that look motley out of the stripe female. Are these truly Motley-Striped since they should carry both genes? And if they do not, then the adult female stripe is a Motley-Stripe (for the offspring to get a homozygous motley pair of genes), and then you run into the same problem.
I think that there MAY be something else influencing these morphs, but don't ask me what! I enjoy the "unknown" factor and would rather wait to see the phenotypic results as they happen.

Serpwidgets
05-27-2002, 03:13 AM
Originally posted by Susan
I don't know what originally started this thread, but I would like to throw a curve into it. I totally agree with serpwidgets genetic explanation of Motley, Striped, and Motley-Striped. However, phenotypically (i.e. how the snake looks) does not always agree with the genetics when dealing with the heterozygous Motley-Stripe.

Yep, I was talking specifically about the genotype. What you've said about the phenotypes agrees with everything I've heard, too. I don't even have one motley in my collection--or stripes, I don't like the looks of striped corns--and it's hard to get information more specific than the fact that the traits are simple-recessive alleles, so I don't feel qualified to comment on the phenotypes of the hets. :)

Some of my other questions are stuff like, "does the 'hurricane' type appearance have any type of inheritance. With Zigzag, the parents with more zigging will produce offspring with generally more zigging." There's a whole ton of questions like that... someday I hope to have some answers.

For now it would be interesting to see lots of pics of offspring from known "het motley/striped" pairs. Seems like there is some partial dominance, with the edge going to the Motley allele. :)

Colleen
05-30-2002, 05:15 AM
I want to thank you sooo much for that great explanation!! I am totally new to this and find learning all of the genetics very confusing. Your example is very easy to understand and follow. I still got lost in the latter posts, but it helped me get a handle on the first step.


:D Thanks
Colleen