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View Full Version : What exactly is a Th. radix "Quad het"



schlangenland
03-28-2007, 03:01 AM
Hi together,
we keep 1,3 Th. radix (bought as) "quad het". The females are Albinos (amel. Iowa), the male is anerythristic. Last year we had hatchlings: snow, albino, anerythristic, wildcoloured 25% each. Snow & albino are both Iowa/ Nebraska- line. I think S. Felzer "created" this name. Maybe someone can help me? How should I name the adults exactly and understandable (but short named) and the hatchlings?:confused:

Thanx a lot. Sincerely.
Thomas:)

schlangenland
03-28-2007, 03:07 AM
Hi together,
we keep 1,3 Th. radix (bought as) "quad het". The females are Albinos (amel. Iowa), the male is anerythristic. Last year we had hatchlings: snow, albino, anerythristic, wildcoloured 25% each. Snow & albino are both Iowa/ Nebraska- line. I think S. Felzer "created" this name. Maybe someone can help me? How should I name the adults exactly and understandable (but short named) and the hatchlings?:confused:

Thanx a lot. Sincerely.
Thomas

here are some pictures of the group:
http://www.schlangenland.de/images/t-radix10.JPG

http://www.schlangenland.de/images/t-radix11.JPG
hatchlings 9/06:
http://www.schlangenland.de/images/radixa1.jpg

Snaky
03-28-2007, 03:12 AM
I think it's like the name indicates they are 4 times (quad) heterozygote. They are heterozygote for: ebraska albino, Nebraska snow, Iowa albino and Iowa snow.

schlangenland
03-28-2007, 03:26 AM
Hi Hans,
thanx for your reply:-) But what about the anerythristic? My first guess was, it's not absolutely scientific, but trivial named: het for snow, albino, anerythristic, wild coulored (=4)... Daniel Grübner (also a member of thamnophis.com, friend of mine from the EGSA) thinks, it's more scientific named: double het for anerythristic +amelanistic Iowa and amel Nebraska (=4)... I already sent a mail to Mr. Felzer... I'm also waiting for an answer from him...
Lots of greetings to belgium.
Sincerely. Thomas:)

ps.: do you get some more cyrtopsis from Jan Gebauer?

Cazador
03-28-2007, 03:33 AM
Quad het just implies that you're dealing with different versions (alleles) for four different genes. Let's simplify things just a bit for discussion by looking at only one gene. If an organism is heterozygous for that gene, it means that it got one allele (let's say a "dominant" allele) from its father, and a different allele (let's say a "recessive" allele) from its mother. Dominant genes normally dictate the appearance (or phenotype) of the animal, so heterozygous individuals look just like individuals that have two of the same copies of the dominant allele (or homozygous dominant individuals). I know that was a mouthful, so in other words, hets look just like non-hets with dominant alleles. Only individuals with two copies of the recessive allele (homozygous recessive) normally have a different appearance (or phenotype).

Getting back to the quad het, you're dealing with at least four different genes that have different alleles (versions of a gene) at all four sites (or loci). Knowing the genetic make-up (or genotype) of heterozygotes is very difficult, even if you keep strict and meticulous records, unless you conduct genetic analysis, which takes sophisticated and expensive equipment. Why? Because hets look just like homozygous dominant individuals. That's why most people talk about the "probability" of having hets.

Here's a link back to one of Scott's web pages where he discusses hets (Scott Felzer's Garter Snakes (http://www.gartersnakemorphs.com/het.html)). I know this is a difficult topic, so hopefully Kitkat (and perhaps others) can take a fresh stab at explaining it more clearly. Hope this has helped, though.

Rick

P.S. The "wild type" or wild color is the dominant appearance (phenotype). It is the opposite of these traits, so it's not counted as one of the "quad" genes that are heterozygous. Also, Daniel's description sounds reasonable, but please let us know what Scott tells you.

Snaky
03-28-2007, 03:48 AM
ps.: do you get some more cyrtopsis from Jan Gebauer?
Yep, normally I will get them on monday :) , 2 new males. I'm also looking for 1 (2) female's and then the breeding group will be complete for me. I'm hoping to borrow a camera next week, so I might post some picture's of some nice cyrtopsis I added to my collection ;).

Well, learned again something. Thanks Cazador.
And now I know I won't buy 66% het's if I want to breed for a morph.

Cazador
03-28-2007, 03:58 AM
Hey Hans,

Just to be clear, that means it looks like a normal individual, but there is a 66% chance that one of its two forms (alleles) of a gene is recessive. It also means there is a 33.3% chance that neither of its alleles are recessive, and you would have bought a completely "normal" snake.

Snaky
03-28-2007, 03:59 AM
It also means there is a 33.3% chance that neither of its alleles are recessive, and you would have bought a completely "normal" snake.
Exactly why I wouldn't buy it if I want to breed morphs;)
(mistyped buy in previous post...)

KITKAT
03-28-2007, 09:46 PM
Anery is necessary to make Snow.

If your snake is het snow, then anery is implied by that. Snakes are not het for wild colored, because wild color is not a recessive gene.


Hi Hans,
thanx for your reply:-) But what about the anerythristic? My first guess was, it's not absolutely scientific, but trivial named: het for snow, albino, anerythristic, wild coulored (=4)... Daniel Grübner (also a member of thamnophis.com, friend of mine from the EGSA) thinks, it's more scientific named: double het for anerythristic +amelanistic Iowa and amel Nebraska (=4)... I already sent a mail to Mr. Felzer... I'm also waiting for an answer from him...
Lots of greetings to belgium.
Sincerely. Thomas:)

ps.: do you get some more cyrtopsis from Jan Gebauer?

KITKAT
03-28-2007, 09:47 PM
Hey Hans,

Just to be clear, that means it looks like a normal individual, but there is a 66% chance that one of its two forms (alleles) of a gene is recessive. It also means there is a 33.3% chance that neither of its alleles are recessive, and you would have bought a completely "normal" snake.

I respectfully disagree. A het is 100% sure to carry a recessive trait.

However a 66% possible het would be what Cazador describes...

Cazador
03-28-2007, 11:36 PM
Once again, Kitkat has saved us from an oversight that I made concerning genetics. One could be 100% sure of having a het (AKA 100% het) by crossing a (homozygous) recessive individual (like an albino) with a 100% normal individual (homozygous dominant). Then all offspring would be 100% hets. One could also cross a (homozygous) recessive individual with a confirmed het. Then 50% of the offspring would be recessive (like albinos) or else they would be 100% het and have a normal appearance (phenotype).

If, however, you breed two hets, you get one aberrant homozygous recessive (e.g. albino), two hets, and one homozygous dominant, but the hets and the homozygous dominant all look alike. All one would know is that, statistically speaking, two of the three wild-type offspring would likely be heterozygotes, giving a 66% chance that they are hets.

A 100% het is certain to have one recessive allele (by definition). Thanks again, Kitkat :).

In order to "design" a quad het, one would probably use two snakes that are double hets for different genes. If one crossed an anery x snow (double het) with an albino x (something else), they would produce a quad het, but this doesn't account for having a melanistic garter in the picture, unless it's unrelated. Also, as Kitkat mentioned, the wild-type is basically the opposite of anery, snow, albino, or whatever, and it is implied (but not counted) when you say you have hets.

Rick

schlangenland
03-29-2007, 03:51 PM
Hi,
thanx for the interesting discussion. Scott Felzer answered me yesterday and here's what he wrote: "Quad hets are created from breeding Iowa snows to Nebraska snows. This cross creates anerythristics which carry the genes for Nebraska albino & snow, and Iowa albino & snow. Breeding quad hets to quad hets produces Iowa snows, Nebraska snows and anerythristics. Hope this helps.Scott"

Sincerely. Thomas

Cazador
03-29-2007, 04:53 PM
That's no fair! He's assuming (unless he's tested) that the gene for the Nebraska albino lineage is different from the gene for the Iowa albino lineage. I don't know if the "snow" trait is controlled by a single gene or if it is the interaction of multiple genes, so I can't speak to that issue. By my way of thinking, an albino, is an albino, is an albino (at least as far as the single gene is concerned... homozygous recessive at a single locus). Isn't that fair to say? It's not my specialty, but something seems amiss.

Thomas... thanks a million for following-up on this.

abcat1993
03-29-2007, 04:55 PM
Ugh, not genes again. Those poor, poor seventh graders.

KITKAT
03-29-2007, 07:27 PM
Not to be defending Scott here... but it is POSSIBLE that the two albino strains are different.

I note that looking at the photos of the two albino lines Scott is working with, that one albino gene seems to mask the wild color of the snake more than the other strain.

Scott Felzer's Garter Snakes (http://www.gartersnakemorphs.com/alplain.html)

Since I have not worked with either, I have no firm opinion.

I do know, however, why the melanistic genes are present in the Schuett strain. Schuett improperly thought that if he bred a melanistic to an albino, he would get snow. That is not how snow is made, and Kyle eventually sold the line to Scott Felzer, who had the anery gene to make the snows.

drache
03-29-2007, 08:33 PM
I still find certain aspects of genetics confusing.
I do know that albinism, as a genetic trait, is separate from the genetics of species and sub-species.

Daniel
03-30-2007, 03:18 AM
Hey guys,

just to put some things right: It is known and proofed that the two amelanistic strains Iowa and Nebraska aren´t compatible to each other.

Snow animals are created when breeding an anerythristic animal to an amelanistic animal and afterwards breeding the offspring to each other so you will recieve babys that are homozygot for anerythristic and amelanistic.

So, if you breed a so named quad het. to another quad het. you will recieve only three different colormorphs: 1. anerythrstics pos het for amel Iowa and amel Nebraska 2. snow Iowa pos het for amel Nebraska 3. snow Nebraska pos het for amel Iowa.

It isn´t really easy to answere the question of Schlangenland. If you want to give your snakes the right name, telling everybody, what genetic potential your snakes might have, you have to write down the long version. Thats the crux, when breeding animals to each other which do have a lot of het-gens.

Your snakes would have to be named: The normal looking: Thamnophis radix het for anery and amel Iowa, pos het for amel Nebraska.
The amel. animals would have to recieve the name: Thamnophis radix amel Iowa, het for anery, pos het for amel Nebraska
or
Thamnophis radix amel Nebraska, het for anery and amel. Iowa
And the snows: Thamnophis radix snow Iowa, pos het for amel Nebraska
or
Thamnophis radix snow Nebraska, het for amel Iowa

That`s it. You can´t summarize this with the addition that your babys are offspring from breeding quad hets. to each other. Especially because the parents aren´t quad hets. as you can see when reading the explanation of Scott Felzer.

Best wishes,

Daniel

KITKAT
03-30-2007, 11:03 AM
Scott writes that when he bred his Iowa albino to his Nebraska albino, the result was wild colored Plains.

Therefore, one of those genes is a true albino, while the other one is something else... but also apparently, both traits are recessive.

Cazador
03-30-2007, 11:38 AM
Hey Daniel,

Thanks for the info. I guess the point of whether the Iowa and Nebraska amel genes are different alleles is a moot point then. I'm almost afraid to mention this, but if they're reproductively isolated from one another, that means... by definition... they're different...

but I don't want to get all wrapped around that issue. It's not worth debating these, essentially lab-produced anomalies that would have an extremely small chance of mating in the wild. In a way, it's a shame that this issue is even arising in the garter snake world :(.

Rick

adamanteus
03-30-2007, 11:40 AM
Yes, indeed!

schlangenland
04-01-2007, 02:55 AM
Hi,
thank you very much for the discussion and the results to my basic question. I can see, that this forum has very experienced and engaged/ interesting members.
The discussion on wild colours/ genetic aberation is an ethic one and for sure worth to be discussed! (but I think: not in this thread). At home we keep about 90% wild coloured reptiles and amphibians and about 10% morphs (incl. garters & corns), and...I like them all. But for sure, I don't want to be seen in the corner of morph fanatics! (hope, my "german english" could express the exact meaning of my thoughts).:eek:
So then: thank you all for your interesting replies!!:-) ...and
... I like the thamnophis.com- forum very much:-)
Thomas;)

Cazador
04-01-2007, 02:33 PM
Hi Thomas,

Your English is VERY clear. Don't worry about it in the least. Best,

Rick