# Co-Dom x Recessive



## GazEmm (Jul 11, 2006)

Let me start off by saying im not sure how well im going to be able to explain what i mean here...but here goes!!

I want to know how to mix co-dom with recessive morphs?

Ill use a ghost boa as my example as this is what im mainly after. If i bred a hypo boa to an anery boa would the results be *hypo ?% het for anery*? and then if i bred 2 of these offspring together (assuming i used 100% hets) would the results then be the ghosts??

I'm assuming my above plan is flawed in many ways as this seems way too easy, so could someone please point out where ive gone wrong?

Im thinking that not ALL babies will by hypo, let alone het for anery...so this narrows down the chances already, then the babies that ARE hypo im guessing are not all going to be het for anery...so again chances getting slimmer

Also, do the same principals apply when breeding any co-dom and recessive morph? i.e. hypoxalbino (sunglow i believe?) and does it also apply to royal pythons (spiderxalbino for example).

Sorry for the long post but ive got limited internet access at work and cant get onto a lot of the sites that explain genetics etc...so im relying on you lot for answers :Na_Na_Na_Na:


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## Plutino (Aug 5, 2007)

co-dom is basically a visual het. A Hypo has one normal gene and one hypo, so half the offspring will get one normal and one hypo. All the offspring that get the hypo will be visually hypo. Anery is recessive so the hets aren't visual, so a visual anery will have 2 anery genes. All the offspring will get one of them, but for the offspring to be visual anery, they need a second.

Breeding a Hypo to an Anery will give half normals 100%het anery
and half Hypos 100% het anery
ie: 
breeding: (hn,nn) with (nn,aa) (first set represents possible hypo genes, 2nd represents possible anery genes
will produce:
nn+an and nh+an
if n = normal, a = anery and h = hypo

the offspring of hypo het anery x hypo het anery will be 25% anery, 75% some form of hypo(25% super, 50% normal), so it's just up to probability which of the % will overlap to give you ghosts ( I believe) The remainder of the non-anerys, 66% will be het anery, but you wont know which ones.

if you breed the nh+an offspring you have the chance for nh+aa = ghost
and hh+aa = super ghost

because it's co-dominant, that means the 'full visual' form of that gene is different just having one (ie nh vs hh = hypo vs super hypo)


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## Ssthisto (Aug 31, 2006)

The rules are simple:

If a gene is DOMINANT then an animal with one copy looks the *same* as an animal with two copies. You can only tell which you have by breeding it to something that does not carry the gene - if you get any normal (non-morph) offspring, your animal is heterozygous for the gene; if you get all morph, you know your animal is homozygous for the gene.
There is some evidence that Hypo (Salmon) in boas acts as a dominant gene - and the "super salmon" is a possible misnomer. SOME super salmons look nicer than heterozygous salmons - but it is not a consistent thing and could be down to other factors.
Spider in royal pythons is almost certainly a dominant gene.

A CODOMINANT/INCOMPLETE DOMINANT gene looks *different* whether you have one, two or no copies of the gene - there are three distinct visual results. Mojave in royal pythons is one of these - a non-mojave animal looks normal, a heterozygous mojave (AKA "Mojave") animal has the pattern and colour change, and a homozygous mojave (AKA Super Mojave or, erroneously, Blue-eyed Leucistic) is a mostly white snake with steel-grey eyes and smoky head markings. 

And a RECESSIVE gene only shows a visual morph if you have two copies of the gene - one or no copies looks like a normal. Anerythristic works like that in Royals, Boas and Corns.

Of course, keep in mind that saying something is a "recessive trait" or a "Codominant trait" or a "Dominant trait" is not fully accurate - for example, "in corn snakes albino is recessive" is not accurate. What IS accurate is "In corn snakes, Albino is recessive to Normal, but is codominant with Ultra." In royal pythons, Mojave is a codominant trait to normal AND to the other genes on the "white snake" complex - it's codominant to Lesser Platinum too, for example.


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## sami (Oct 23, 2006)

Taking Ghost boas as your example:

hypo x anery

approx 50% of the litter would be hypo. All of the litter would be 100% het anery.

Holdback salmon 1000% het anery and grow on.

Anery x salmon 100% het anery and you have your ghost boas (well the chance of ghost boas).

To make your bosts you need the anery gene on both sides and the hypo gene on one or both sides.

mason


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## GazEmm (Jul 11, 2006)

Thanks for the replies, got it sussed now.

I havnt been looking long but i havnt seen many anery boas or hypo het anery boas up for grabs (maybe im looking in the wrong places mind).

Do these come about often? Im thinking i may be better off just getting a ghost boa to start with :lol2:


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