Are We Using the Correct Genetic Labels

[bohannbj]

Before I go into this I want to say that I wouldn't know more than basic genetics if I didn't get to teach it. I have noticed that a lot of breeders useing terms like line bred, codominate, and incomplete dominance (rarely), but the breedings don't seem to always work this way. I would like to offer up what knowledge I have, about a few of these inheritance patterns.

Line bred- Line bred is not a type of inheritance but rather a breeding method for increasing a polygenic trait. So let's say you had ten slots to fill with either yellow or tangerine, the more you fill with a particular color the more intense it would be.

Codominance- This trait works just as though it were two dominate traits acting at the same time. The book uses the pairing of a black chicken and a white chicken. Both colors are dominate so when bred together they produce a checkerboard chicken.

Incomplete Dominance- This trait is usually explained through the crossing of a white rose and a red rose. The offspring in this pairing (F1) all turn out pink, but if you breed the F1 back to each other it yeilds 25% red, 25% white, and 50% pink.

I persosnally think that we have labeled some traits as codom when they are in fact incomplete dominance. If anyone has breeding records they would share with me, I would like to compile a database.
Brent

 

[Sandra]

You are totally right. The traits we refer to as 'codominant' are, in fact, incomplete dominant (right now there aren't any known codominant traits in leopard geckos). The only reason why people who know still use the 'codominant' word instead of 'incomplete dominant' is because it's deeply-rooted between the hobbyists (I'd like to know who's the genius who started it) and there's already too much confusion and misleading information about this topic to start changing terms.

Right now is not a big deal, but we'll see when real codominant traits start appearing in reptiles...

It's nice to know there's a genetics teacher between us

 

[bohannbj]

I agree that there is a lot of confusion within the hobby. I think we need to start correcting the problem now because the leo trade is only going up in numbers. As more snake laws restrict pythons and more parents find out that leos are easy to care for and don't cause allergies, leos will be as common as fish. I just feel that the earlier we fix the problem, the easier it will be. Alas, nothing in this world is ever easy.

 

[GeckoRing]

I am fairly new to genetics, and this has been extremely confusing to me, especially in regards to in use with the snows. If it was co-dom, and you breed a snow to say a SHCT, wouldn't you end up with a snow with orange spots, or a tangerine with white and black spots? Sometimes you end up with a pastel snow, so would that make it incomplete dominance?

 

[bohannbj]

That's correct; however, I don't think macks are codom. By the difficulty people seem to be having with producing the supers I would say that it is incomplete dominance. You should also remember that color is most likely working on more than one level, so the amount of white is probably polygenic. I feel sorry for all the people that bought macks thinking they could produce snows fairly easy and now they are waiting an extra year.
Brent

 

[GroovyGeckos.com]

I feel sorry for all the people that bought macks thinking they could produce snows fairly easy and now they are waiting an extra year

Why can`t someone produce Mack Super Snows easily? Hatching female Macks(and maybe supers), I am pretty sure, has been the only setback producing the SS.

It is as easy as breeding two Macks together, and you get a 25% chance, for each egg. That does not equate to "1 in 4 babies will be SS". Or you can breed a Mack to a Super, and you get a 50% chance, for each egg. SS X SS= 100% Super Snow.

It is actually incomplete dominance, and not everyone has caught on to the fact, due to them being labeled "codoms" in the first place. You are right, it is an ignorance issue. Since co-dom it is a shortened word, I was guilty myself. lol

I actually thought it was short for incomplete-dominance, when we were first introduced to them. Then of course, I did some reading and found out there were two different types. It was a little confusing!

 

[GroovyGeckos.com]

I am fairly new to genetics, and this has been extremely confusing to me, especially in regards to in use with the snows. If it was co-dom, and you breed a snow to say a SHCT, wouldn't you end up with a snow with orange spots, or a tangerine with white and black spots? Sometimes you end up with a pastel snow, so would that make it incomplete dominance?

No. I do not think you could count on orange, since that is a linbred trait. The normal appearance, is what you would see "blended" with the Snow gene instead. Some geckos would inherit the orange, and some may not.

That is one of the things that made it confusing to me, because a non-super Mack, to me could also (possibly)be viewed as a "combo" of the Snow, and normal, because most of them also display yellow/normal-ish color when they get older. Then we have the Mack "Pastels" which also look like a "combo" of normal and snow. There have even been geckos that display both the "Pastel" and non-super Snow traits upon hatching. I guess just to keep us guessing. lol

 

[SteveB]

I have this information on my website...

Here are some commonly used terms and their definitions

het·er·o·zy·gous
adj.

1: Having different alleles at one or more corresponding chromosomal loci.
2: Of or relating to a heterozygote.
-------------------------------------------------------------------------------------
ho·mo·zy·gous
adj.

Having the same alleles at a one or more gene loci on homologous chromosome segments.
-------------------------------------------------------------------------------------
co·dom·i·nant
adj.

Of or relating to an equal degree of dominance of two genes, both being expressed in the
phenotype of the individual.
-------------------------------------------------------------------------------------
dom·i·nant
adj.

1: Exercising the most influence or control.
2: Of, relating to, or being an allele that produces the same phenotypic effect whether
inherited with a homozygous or heterozygous allele.
n.
3: A dominant allele or trait.
4: An organism having a dominant trait.
-------------------------------------------------------------------------------------
incomplete dominance
n.

1: A heterozygous condition in which both alleles at a gene locus are partially expressed
and which often produces an intermediate phenotype.
2: the property of being expressed or inherited as a semidominant gene or trait

 

[okapi]

The co-dom craze came from that one guy who breeds tremper albinos.
Giants would be considered incomplete dominant IMO, but he was looking at ball python breeders and their co-dom morphs when he hatched those. Then everything that hatched with a visible het form after that just added to the co-dom craze.

 

[SteveB]

The blame is not only on that one guy but on everyone who ran with it. Every year he makes certain claims and every year we climb on the bandwagon to sell hets before any of us have proven the genetics out ourselves.
We're all so busy trying to make names for ourselves that we won't allow for any cooperation. I mean just try to explain the different Snow bloodlines right now to any outsider. Most of us don't even have a clue what's going on with that!

Breeding these animals is a luxury. These are mass produced mass market animals. And that's part of what drives the naming mess. Everyone is afraid of admitting that they are producing exactly what anyone else can produce and in many cases can buy from PetCo for $19.99!
Look what adding a name does to the value of these animals. And "that one guy who breeds tremper albinos" is a master of this. He knows we'll pay for it. He knows we want to believe in it. And he knows that any sale he makes at these inflated prices is just icing on the cake, because he knows how to mass produce them just as well as he can market them.

 

[bohannbj]

I have to agree when it comes to the "emerine". What I can't understand is why people are so secretive with their breeding results. I know its a business, but why not share pairings and results. Having incorrect labels and selling stuff as hets when they are not is bad for everyones business. Casual collectors don't become major collectors if their $200 pair only produces $35 normals. Call it a request or a plea, but I wish there was a forum for posting pairing statistics.
Brent

 

[Sandra]

This market is based on feedback. Who does buy high end geckos? The person that only wants a pet? No, it's the breeders the ones who buy, and the ones you might be buying from tomorrow. If there weren't any rival (in the best sense of the word) breeders, the gecko market wouldn't exist.

Expreading misleading information and being secretive about your experiences might be beneficial at first... But in the long term, wouldn't it be best that there were plenty of knowledgeable breeders? There would be more potential buyers, and the quality of the animals would improve due to competence.

That's why I try to share all my knowledge and experiences (even if they are not many...) and admire the breeders who do so. Well, that's my opinion.

 

[SteveB]

The problem is that people see how easy it is to breed leopard geckos, and see those high prices, suddenly EVERYONE is a breeder.
And everyone you sell to is your competitor the very next year.
Look at the debate that was raging here about how long before enigma prices drop.

 

[bohannbj]

I understand that people in this site are in a "kinda competition." However, I would venture to say that there are only 40 people that are serious about commercial breeding on this site. That number isn't even as many states in the Union, not to mention all of our wonderful international friends. I'm not sure what the Euro market is like (let me know Sandra), but I would guess that it is starting to boom as well. My point is that small time collectors will never become big timers, if their first pair don't produce what the breeder said they would. In the end a happy customer is a returning customer, just ask Phil and Christine at GKO.
Brent

 

[Sandra]

I cannot tell all that well about European contries because all of them speak different languages... To know how are things going it's not as easy at it is in the USA.

In northen countries the market was already quite good, although of course it cannot compare to the American. I don't know about southern countries... But at least in Spain, there aren't any reputable breeders. Most people who breed leos are just doing it because it's easy, the kind of people that buy some pairs and start breeding right away without expecting any definite results (makes me almost feel stupid when it took me two years and a half from getting my first gecko to even think about breeding).

However, some people seem to be starting to care about getting high quality geckos and breeding for objectives and not only to mass produce. I guess that in some years we won't be too different to the rest of the countries.

For me, informing people in my country is almost necessary if I want to sell something in the future.