Genetics....

[TessadasExotics]

Toffino is not a gene. Toffino is the appearance of a ball python that has a gene pair made up of a toffee gene and an albino gene. The identy of the genes and the identity of the snake's appearance are two different things. Another example of this is a ball python with a mojave gene paired with a lesser gene. The appearance of such a snake is blue-eyed leucistic.

If toffino was a gene, then toffino snakes would be able to breed true. But toffino mated to toffino always produces albino, toffino, and toffee snakes.

I looked up compound heterozygous. http://en.wikipedia.org/wiki/Compound_heterozygosity I am not too happy about using the term. Mostly because it is another piece of jargon for newbies to learn and misuse. NERD is expanding the meaning to any gene pair in which the two genes are not the same and neither gene is a normal gene. Which leads to confusion with visual het -- any gene pair in which the two genes are not the same and the creature does not look normal. IMO, it is easier to simply identify a gene pair by the genes -- lesser/mojave, normal/albino, albino/albino, normal/normal, etc.

I like the gene symbol system at http://www.informatics.jax.org/mgihome/nomen/gene.shtml (See sections 2.3 and 3.1 in particular.) The mouse geneticists have answered nomenclature questions than herper geneticists haven't imagined yet.

Gene pairs with two different genes that are both recessive to the normal gene have already turned up in several species of snakes -- reticulated pythons, corn snakes, boa constrictor, and others. There are hundreds of them in the lab mouse. I have no doubt that more will be found in snakes, eventually.

This and some of the other stuff some people here try to say is doing the same thing. This hobby already has way too many things wrong with it. Why compound this further for others? Yes technically all single gene morphs are Het for the "super" Homo form. You calling a mojave a het is not helping matters. Just like someone else who is trying to say that a Banana isn't a banana but a het and that a super Banana is actually a Banana. That's pretty ignorant imo. A Banana is a Banana and a super Banana is a Super Banana.
The Toffino is a recessive genetic combination that works just like Super Stripe, Vanilla cream or mojave/lesser and a few other combos. The only difference is that its a recessive.

[paulh]

This and some of the other stuff some people here try to say is doing the same thing. This hobby already has way too many things wrong with it. Why compound this further for others? Yes technically all single gene morphs are Het for the "super" Homo form. You calling a mojave a het is not helping matters. Just like someone else who is trying to say that a Banana isn't a banana but a het and that a super Banana is actually a Banana. That's pretty ignorant imo. A Banana is a Banana and a super Banana is a Super Banana.
The Toffino is a recessive genetic combination that works just like Super Stripe, Vanilla cream or mojave/lesser and a few other combos. The only difference is that its a recessive.

You know, if we simply listed the two genes in a gene pair, we could dispense with the terms heterozygous, visual het, and compound het.

The point that I was trying to make is that toffino is a combination of genes. If toffino was a gene, then it would be possible to have snakes with 2 toffino genes. Mating a snake with two toffino genes to another snake with two toffino genes would produce only snakes with two toffino genes. This does not happen. The dominant/codominant/recessive classification results from the comparison of two genes that can form a gene pair. Both albino and toffee genes are recessive to the corresponding normal gene. As toffino comes from a gene combination and not a gene, toffino cannot be a recessive.

I agree with the statement that a Banana is a Banana and a super Banana is a Super Banana.

Definitions:
http://ghr.nlm.nih.gov/glossary=genotype
A genotype is an individual's collection of genes. The term also can refer to the two alleles inherited for a particular gene. The genotype is expressed when the information encoded in the genes' DNA is used to make protein and RNA molecules. The expression of the genotype contributes to the individual's observable traits, called the phenotype.

http://ghr.nlm.nih.gov/glossary=phenotype
A phenotype is an individual's observable traits, such as height, eye color, and blood type. The genetic contribution to the phenotype is called the genotype. Some traits are largely determined by the genotype, while other traits are largely determined by environmental factors.

The trouble is that herpers play very loosely with the concepts of the genotype and the phenotype. A banana ball python displays the banana trait (phenotype) because the gene pair is made up of a normal gene and a banana mutant gene (genotype). A super banana ball python displays the super banana trait (phenotype) because the gene pair is made up of two banana mutant genes (genotype).

When we breeders are predicting the results from a given pair of snakes, we need to know the snakes' genotypes. That is why we call a normal-looking snake (phenotype) a het albino (genotype) if the snake has an albino mutant gene paired with a normal gene. Or call a ball python with two pinstripe genes a super pinstripe even though it looks like a pinstripe ball python (which has a gene pair made up of a pinstripe mutant gene and a normal gene).

IMO, we ought to list a ball python's genotype and phenotype when we write.

[Family Jewels]

IMO, it is easier to simply identify a gene pair by the genes -- lesser/mojave, normal/albino, albino/albino, normal/normal, etc.

I didn't mean that "compound heterozygote" should be promoted as common terminology for bp breeding. I just found the term personally helpful in understanding how to attribute genotypes for compatible morphs in a Punnet square (using ta instead of ttaa, or TtAa). Mouse breeders have a better foundation (terminology-wise) and I actually wanted to use the superscripts for the allelic traits...I just couldn't figure out how to do it in this forum. I'm genuinely curious as to what mouse breeders use in the place of "compound heterozygote" (if anything?). In normal conversation however, I completely agree that lesser/mojave, normal/albino is most practical.

NERD is expanding the meaning to any gene pair in which the two genes are not the same and neither gene is a normal gene. Which leads to confusion with visual het -- any gene pair in which the two genes are not the same and the creature does not look normal.

While I agree that NERD is expanding the meaning a little from the Wikipedia page on medical genetics, I don't think it's that far off at all. A compound heterozygote is when two mutant alleles pair up at the same locus to create a new (and exaggerated) phenotype. This is completely different from a single-mutation visual het in which one of the alleles is the wild type, and you're only dealing with a single mutant allele. This is really not any different from the medical definition.

Description describing a genetic disorder in humans----

"When a person has one mutated copy, he or she is called a carrier or heterozygote. When a person has two of the same mutated copies, he or she is called a homozygote. When a person has two different – but mutated – copies, he or she is called a compound heterozygote."

What's happening at a molecular level is that the normal allele has a modifying effect on the mutant allele. In other words, the normal allele tries to "pick up the slack" as much as possible. However when both alleles are mutant (i.e. typically causing some enzymatic pathway to malfunction), then there's nobody around to pick up the slack. There is no modifying influence from a normal allele. This "doubling up" of mutant alleles can occur as a homozygote (albino) or as a heterozygote (toffino)... and even though I would never try to explain any of this to someone who doesn't care about genetics, I personally find it fascinating.

[TessadasExotics]

I agree mostly with the both of you, family Jewels and paulh.

How ever I do not think we should add 2 gened names to things such as a Banana, Mojave or what have you. There is no need to say a Mojave is a Normal/Mojave. Or that a Banana is a Banana/Normal.
Lets keep it simple for people to understand. Heck most new people take a few months or years to even understand the normal stuff as it is. Banana is Banana , Mojave a Mojave and etc lol!
Now when one is talking about a BEL that is comprised of 2 different genes then yes, we should list both genes as otherwise who would know?

[paulh]

Family Jewels:

Two ways to indicate a superscript.

1. A lot of text editors will not do superscripts. In that case, set it off with a ^ character. In math, 3^3 equals 3² equals 3 squared equals 9. The symbol c^ch means c with ch as superscript.

2. Some forums have editors that will do superscripts. c^ch. This one does do superscripts. Start the superscript with a <left bracket character>sup<right bracket character>, and end the superscript with a <left bracket character>/sup<right bracket character>. The left and right bracket characters are the two keys just to the right of p key on my keyboard. [ and ].

I find these things fascinting, too.

[paulh]

I agree mostly with the both of you, family Jewels and paulh.

How ever I do not think we should add 2 gened names to things such as a Banana, Mojave or what have you. There is no need to say a Mojave is a Normal/Mojave. Or that a Banana is a Banana/Normal.
Lets keep it simple for people to understand. Heck most new people take a few months or years to even understand the normal stuff as it is. Banana is Banana , Mojave a Mojave and etc lol!
Now when one is talking about a BEL that is comprised of 2 different genes then yes, we should list both genes as otherwise who would know?

I would like to keep things as simple as possible. But how can I explain why mojave mated to mojave does not produce 100% mojave babies without using genes? After all, albino mated to albino produces 100% albino babies. What makes a mojave x mojave mating different from an albino x albino mating?

I'd be interested in your take on a minimum list of genetics jargon. I don't think I could get by without dominant, codominant, recessive, normal, mutant, gene and gene pair. Should morph, base morph, and super be added? I am assuming that most forum attendees know what cell, egg, sperm and trait mean.

[jdhutton2000]

Wow... should have kept up with this debate! LoL. I think in the end, saying het Mojave is wrong, because it would be het BEL (grey head)... het would be in reference to the "super" or homozygous form of the gene. Like Paulh was saying people are confusing phenol and geno types.
Now I will also say that when we are on a Ball Python genetics forum, using proper genetics terms, especially when that was the sole purpose of this thread was to talk about the ambiguity between real and BP genetics.

[paulh]

And "het BEL (grey head)" is another example of confusing phenotypes and genotypes. BEL (grey head) is the phenotype produced by a gene pair made up of two copies of a mutant gene named mojave. Mojave is the phenotype produced by a gene pair made up of a normal gene and a mojave mutant gene. I'd agree with het BEL (grey head) designation if the mutant gene was named BEL (grey head).

I think it is easier to parallel nomenclature between recessive, codominant, and dominant genes (as the pro geneticists do) than to make it up as we go along.

Two genes can make three gene pairs.

Albino is a mutant gene that is recessive to the corresponding normal gene.
Genotype = Two normal genes = homozygous normal. Phenotype (appearance) = normal.
Genotype = One normal gene and one albino gene = heterozygous albino. Phenotype (appearance) = normal.
Genotype = Two albino genes = homozygous albino. Phenotype (appearance) = albino.

Mojave is a mutant gene that is codominant to the corresponding normal gene.
Genotype = Two normal genes = homozygous normal. Phenotype (appearance) = normal.
Genotype = One normal gene and one mojave gene = heterozygous mojave. Phenotype (appearance) = mojave.
Genotype = Two mojave genes = homozygous mojave. Phenotype (appearance) = BEL (grey head).

Pinstripe is a mutant gene that is dominant to the corresponding normal gene.
Genotype = Two normal genes = homozygous normal. Phenotype (appearance) = normal.
Genotype = One normal gene and one pinstripe gene = heterozygous pinstripe. Phenotype (appearance) = pinstripe.
Genotype = Two albino genes = homozygous pinstripe. Phenotype (appearance) = pinstripe.

As it is now, just giving the phenotypes in a breeding problem requires translating them to genotypes before doing the problem. That can stop a newbie cold, even one who is familiar with the principles of genetics. Giving the genotypes allows anyone familiar with the principles of genetics to get the correct genotype answer to the problem even if that person is unfamiliar with the names to the corresponding phenotypes.