Peach * Cameo

It will depend on the sex of the male bird.. He will determine The color in this case.. There is always a possibility of some throw back on the peach and cameo.. I have hatched both Cameo and peach from the same split male. If the male is peach the female chicks will be peach out of the cameo hens and the male could be split to peach and cameo. .
 
I've explained it before, but I'll do it again.

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Imagine you're looking at a Z chromosome. At one point on the chromosome lies the gene that, when mutated from the normal version, gives rise to the Cameo color. At another point on the chromosome lies the gene that, when mutated from the normal version, gives rise to the Purple color.

The first Peach female was bred from a male who was IB split to Cameo and Purple. This means that one of his Z chromosomes had the Purple gene, and the other Z had the Cameo gene.

During the meiosis that leads to sperm formation, the cells divide and replicate their chromosomes, and during this process, chromosomes line up with the other member of their pair, and often wrap over themselves and exchange parts. This phenomenon is called "crossing over" and results in a reshuffling of chromosome parts. Thus the top part of one is exchanged with the top part of another, and you end up with a newly combined chromosome in a sperm or egg cell. Chromosomes passed down to offspring are often a new combination of parts from each member of the pair in the parent.

When this occurred in the male that fathered the first Peach peahen, his two Z chromosomes crossed over, and instead of simply passing down one Z with Purple OR one Z with Cameo, some of his sperm contained a Z with Purple AND Cameo on the same chromosome, and some sperm contained a Z with neither mutation. When a sperm with BOTH mutations on the Z chromosome fertilized an egg, the result was the first Peach peahen. When a sperm with NEITHER mutation on the Z chromosome fertilized an egg, the result was a normal IB hen (see "History of the Peach" on Brad Legg's site, and I also discussed this with the original breeder, Clifton Nicholson).

The only way a male split to Purple and Cameo could have a normal IB daughter is if crossover occurred on his Z chromosomes, giving rise to a sperm that contained a Z chromosome with neither mutation on it. Likewise, it could just as easily occur that a sperm contained a Z chromosome with both mutations on it, and this is what describes the sperm that fertilized the egg which gave rise to the first Peach peahen.

This establishes that Peach is the phenotype which occurs when peafowl have both the Purple and Cameo mutations present on the same chromosome. This means that a Peach male is homozygous for Purple AND Cameo, and if he is bred to a Cameo female, he will have Cameo sons split to Peach, and Peach daughters. This is how it works:

The Peach male has 2 Z chromosomes, each with Purple and Cameo on it. The Cameo female has only one Z chromosome, with Cameo on it, as well as a W chromosome. When they mate, they give one from each pair. The male can give only a Z, and in this case, either of his Zs will carry both Purple and Cameo. The female can give either a Z or a W, and her Z has Cameo on it.

Thus sons receive one Z with Purple and Cameo on it (i.e. "Peach") from Dad, and one Z with Cameo on it from Mom. Since they don't have two copies of Purple, that color won't show. But they do have two copies of Cameo, so it will show. One of their Zs has just Cameo, and the other has Cameo and Purple together (which results in Peach), so they will be Cameo split to Peach.

If one of these males is bred to a normal IB female, half of the daughters will be Cameo, and the other half will be Peach. We'd say he's "split to Peach" rather than "split to Purple" because to be split to Purple, he'd have to have one Z with Purple only -- no Cameo as well, since when they travel together, they're called "Peach."

If we reverse the breeding and do Male Cameo X Female Peach, the sons will be the same -- one Z with just Cameo, and the other with Cameo and Purple. Since they have two copies of Cameo, they will look Cameo. But in this case, the daughters will get only Cameo from their dad, so they will be Cameo.

And for those who still assert that Peach is a separate mutation from Cameo and Purple, here's the test -- if you bred Peach with either Cameo or Purple and all three are REALLY separate genes, then all the male offspring would look IB no matter which way the cross is done. It would be the same as crossing Cameo and Purple -- all sons will look IB but be split to both (as was the father of the first Peach peahen). If you don't get IB-looking sons from Peach X Cameo or Peach X Purple, then the "Peach is a separate mutation" hypothesis is disproven.
 
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i have bred purple and peach never got any cameo.......repeat i have never hatch any cameos.......

Of course you wouldn't. If you bred Purple and Peach, all you'd get is Purple and Peach. And if you bred Cameo and Peach, all you'd get is Cameo and Peach. But if Peach is a separate mutation, then if you breed Purple and Peach (or Cameo and Peach) you'd get only IB sons and daughters colored like the father.

Purple Male X Peach Female = 50% Purple split to Peach Males, 50% Purple Females

Peach Male X Purple Female = 50% Purple split to Peach Males, 50% Peach Females

That is what you'd get if Peach is genetically Purple-Cameo.

If Peach is a separate mutation, then all the sons will be IB colored. If you bred Purple with Peach and got NO IB-colored sons, that proves that Peach is not a separate mutation, because if you bred Purple and Cameo, you WOULD get IB-colored sons.

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I'll try to explain it further.

Purple and Cameo are sex-linked recessive mutations. They are called "sex-linked" because the genes are located on the Z chromosome. They are called "recessive" because when the "normal" version of their respective genes is present on the other chromosome in a matched pair, Purple and Cameo will not be expressed. Because females have only one copy of the Z chromosome, there is no "other chromosome in a matched pair" which can have the normal version of this gene. Thus females need only one copy of either Purple or Cameo to be expressed. Males, however, have two Z chromosomes, so if they have one Z with the normal version of either the Purple or Cameo gene, then the colors won't be expressed.

Now we have Peach, which is the result of the dual expression of Purple and Cameo. Why do I come to this conclusion? Because of breeding results which do not fit the model of "Peach" being the result of a separate, independent mutation. If Peach was a separate gene, then Peach Male X Purple Female would give IB-colored sons, just as Cameo Male X Purple Female does. I have gone over this already, so I won't again.

For a bird to be "Peach" then both Purple and Cameo must be expressed. For either to be expressed, there needs to be no "normal" version of either gene present on "the other chromosome in a matched pair." Since females don't have another Z, they can't be heterozygous -- but males can be.

OK, so we have a Peach male. Genetically, he has two copies of Purple and two copies of Cameo. A Peach female has only one Z, so she has only one copy of Purple and one copy of Cameo.

So what happens if a male has two copies of Cameo and one copy of Purple? Well, he won't be Peach, since being Peach requires the dual expression of Purple and Cameo. OK, so what color WILL he be? Well, if he has two copies of Cameo, then Cameo will be expressed. Because he has one copy of Purple and one copy of the "normal" version of that gene, Purple won't be expressed. Peach (2 Cameo + 2 Purple) minus 1 Purple = Cameo split to Peach.

Why is he "split to Peach" instead of "split to Purple"? Well, because the Purple and Cameo are on the same chromosome. Purple can't be passed down by itself in such a male, because even if his Z chromosomes cross over again, the other copy of Cameo will come over. In other words, the only way for him to pass down Purple without Cameo is if he had a "normal" version of the Cameo gene available for crossing over, and he doesn't (if he did, he wouldn't be Cameo colored -- he'd be IB split to Peach). So he can pass on either the Z with Cameo and the "normal" version of the Purple gene, OR the Z with Cameo and Purple.

He has two copies of Cameo, so he appears Cameo. But one Z has both Cameo AND Purple. Since Cameo + Purple = Peach, this means that he is split for Peach. Put it all together -- he's Cameo split to Peach.


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Regarding Peach, Purple and Cameo, these are some breeding results:


Purple Male X Cameo Female = 50% IB split to Purple and Cameo Males, 50% Purple Females

Cameo Male X Purple Female = 50% IB split to Purple and Cameo Males, 50% Cameo Females


Peach Male X Cameo Female = 50% Cameo split to Peach Males, 50% Peach Females

Cameo Male X Peach Female = 50% Cameo split to Peach Males, 50% Cameo Females


Peach Male X Purple Female = 50% Purple split to Peach Males, 50% Peach Females

Purple Male X Peach Female = 50% Purple split to Peach Males, 50% Purple Females


And recall the information from the "History of the Peach" -- IB split to Purple and Cameo Males will have mostly Purple and Cameo daughters, but due to crossing over, will throw occasional IB and Peach daughters. That breeding result is completely in line with well-documented inheritance studies in many species with regards to linked genes (i.e. separate genes existing on the same chromosome, as with Purple and Cameo existing on the Z).



This is based on information I've gathered from talking to a few breeders, reading their and other websites, and deciphering a pattern of inheritance from that information and my knowledge of genetics overall. Note the difference between the first two crosses and the rest -- Purple and Cameo are separate genes, and crossing them results in IB sons split to both colors. If Peach was a unique mutation, it would follow that same pattern of inheritance -- but it doesn't. If you want to predict offspring from planned crosses, you need to know how the colors are inherited.

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