Reptile & Amphibian Forums

I'm new to this game, but have a background in biochemistry and genetics. This is why I am puzzled...

I see lots of talk about "proving out" things but have never heard of a super spider or super pin that carry 2 copies of the gene. Using theoretical genetics, if a spider is bred to another spider, there should be 1/4 of the babies that are homozygous for the spider gene. Each of their offspring should be a spider.

I have done searches and cannot find any info on a super spider (even if it does exist).

Has anyone tried to take the babies from a spider x spider (or bee) and proven that they have a homozyogous spider rahter than just a heterozygous spider?

If they don't exist it raises some very interesting questions about the viability of homozygous spiders and could be explained by imparied neural development caused by the gene that leads to the wobble.

Any info would be greatly appreciated.

There are no super spiders or super pinstripes they are dominant not codominant. I believe that dominant genes are homozygous anyway, but I could be wrong.

nice try but bhb has had a homo pin for at least a few years.

another week, another spider thread yippie
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The previous response was dead on. There is no "super" form of spiders or pins. They are a Dominant gene(NOT Co-Dominant). So if they carry the gene it shows up in a homozygous form. There is no Hets with Dominant, Hets only are represented with Recessive. "Supers" only show up with Co-Dominant genes. So if it has the Spider gene it shows, and thats how far the gene goes. Hope that cleared it up for ya.

Not necessarily, if it was dominant then all offspring would be Spiders or Pins. It can't be dominant and produce a percentage of normals and a percentage Of Spiders or Pins, that would make it co-dominant. This is a good definition of dominant:
A gene that is expressed phenotypically in heterozygous or homozygous individuals.
Eric

All the babies do end up being spiders if you breed spider to spider. If you breed spider to normal then half the babies come out spider. It's because it takes a gene from the mother and the father. Then there's some stuff about the alleles and other stuff that I don't know much of anything about.

You can have heterozygous or homozygous dominant genes expressing same phenotype. That is it's possible spider could be either heterozygous or homozygous dominant.

Dr Peter Kim

I must ask how. I know how Spiders and Pinstripes work, very proficient with Ball python genetics. Also know that not much has been done to prove that there is no super form. But, just want to know how something dominant such as a wild type or "normal" only produces normals, so to speak, yet Spiders and Pinstripes being "dominant" can also produce normals. Just a question. Want to know if there is a definite answer.
Eric

A normal gene is dominant over many of the color mutations (it's not dominant over spider or over pinstripe). An animal that looks "normal" (normal phenotype) could be homozygous for the normal gene or heterozygous for the normal gene. In both cases the animals would look normal although genetically they will be different (they will have different genotypes). That is why you can have an animal that looks normal, but is heterozygous for let's say the pied gene. Accordingly, not all phenotypically normal animals will produce normals only. That depends on their genotype. If they are heterozygous for a recessive gene they might produce animals with that phenotype if crossed with another carrier.

Now, Spider, and Pinstripe are dominants. It seems that all animals that are phenotypically Spider or Pinstripe are heterozygous for that particular gene. Since the other gene in that locus is normal, they produce both normals and Spiders (or Pinstripes), even if paired with another Spider (or Pinstripe). Since they are not Co-dominants, there are no Super-forms. In theory there would be homozygous Spiders and homozygous Pinstripes, but since it seems that nobody has produced clutches that are ALWAYS Spiders or Pintripes from the same animal, the consensus sees to be that the Spider gene and the Pinstripe gene are lethal in homozygous form. By chance you might get an ALL Spider or an ALL Pinstride clutch and that wouldn't prove that they are homozygous. It would have to be a 100% Spider (or Pinstripe) ALL THE TIME.

I don't know if people tend to have a lot of dead babies from Spiders or Pinstripes. If so, that could be the proof that these genes are lethal in a homozygous form. Or maybe the embryos die in the early stages of development, right after fecundation and never make to the egg stage.

Hope this help, but I would like to know if people really get a lot of dead babies from Spiders and Pinstripes.
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Sed et serpens erat callidior cunctis animantibus terrae quae fecerat Dominus Deus...

Seems to me that this thread needs definitions:

All gene pairs are either homozygous or heterozygous:
Homozygous = 1. the two genes in a gene pair are the same. Examples: Two normal genes, two albino genes, two mojave genes, etc. 2. A creature with a homozygous gene pair.

Heterozygous = 1. the two genes in a gene pair are NOT the same. Examples: A normal gene and an albino gene, a normal gene and a pinstripe gene, a mojave gene and a lesser platinum gene, etc. 2. A creature with a homozygous gene pair.

All genes are either normal genes or mutant genes:
Normal = wild type = 1. The most common appearance among the members of the wild population. 2. The most common gene at a given location in the chromosomes in members of the wild population.

Mutant = 1. NOT the most common appearance among the members of the wild population. 2. NOT the most common gene at a given location in the chromosomes in members of the wild population.

All mutant genes are either dominant, recessive or codominant to its normal alternate gene:
Dominant = A mutant gene which produces an abnormal appearance when homozygous (two copies of the mutant gene) and the same abnormal appearance when heterozygous (a mutant gene paired with a normal gene). The genes present CANNOT be inferred from the creature's appearance.

Recessive = A mutant gene which produces an abnormal appearance only when homozygous (two copies of the mutant gene). The creature looks normal when the gene pair is heterozygous (a mutant gene paired with a normal gene). The genes present CANNOT be inferred from the creature's appearance.

Codominant = A mutant gene which produces an abnormal appearance when homozygous (two copies of the mutant gene) and a different abnormal appearance when heterozygous (a mutant gene paired with a normal gene). The genes present CAN be inferred from the creature's appearance.

Paul Hollander

Very clear definitions!
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Sed et serpens erat callidior cunctis animantibus terrae quae fecerat Dominus Deus...

I have heard that BHB has a Pin that produces all Pins. I beleive there is not much done with this because if there is a super, then it looks just like the non-super; that being said you would have to keep back all baby Spiders and Pins and then breed them all to find out which one is the super. Lots of hassle. I know if I have female Spider or Pin that is breedable I have a stable of males for them, other than Spiders and Pins. Just my opinion, but if someone was doing for research purposes then it could be feasible.
Eric

Btw : there is a lot of stupid answer here. Or people who just don't know what they are talking about (happens to me to sometimes).

You can have a super spider or super pin that will look just like a normal spider or pin. But will reproduce only spider or pin.

There is no super spider as far as we know. Kevin from Nerd tried to hit many times but never been successful.
Otherwise, not many people cross spider together, since it's unnecessary to produce the morph people want. If it happens, it's more "luck" than anything. Only reason you would put 2 spider combo together is to increase your odds on spider combos.

Lastly, I heard BHB have a pin that reproduced many pin in a row without any normal. Not sure if that's just a rumor (never been confirmed) but it would make sense.

I think the super spider is impossible and they just don't survive to the birth. but IMO spider should have never been reproduced.
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love this world, don't hate it.

Welcome! Glad to have another with a genetics background.

You have good questions. I have not worked with either pinstripes or spiders, but I have tried to follow the posts on this and other forums. I can't answer your questions, but there has been speculation that spider is lethal when homozygous.

Do a search in this forum for "Randy Remington". He seems to be among the most sensible of the speculators.

Paul Hollander