White Crested Black Polish Question

[Amer]

Generally a bird will be black in all of the places where melanin belongs. Or, if diluted, a color such as white or blue will replace the black. But it doesn’t show up in patches, white in some areas and black in others. So why don’t white crested black polish not follow these rules? Is the crest coloring considered a pattern?
And it’s not a crest thing, either. There are solid black Polish, Crevecoeurs, and Silkies. (Honestly with all of the silkie colors I’m surprised no WCB Silkies exist.)
So what are the genetics behind it?
An explanation on the black crested white would be appreciated too.
@nicalandia

Thank you!

 

[AltonaAcres]

Lol, good question! I'll follow to see the answer.

 

[nicalandia]

An explanation on the black crested white would be appreciated too.
@nicalandia

Thank you!

I've done an extensive research on the matter and will be posting my take on the matter(with very little research to back it up since there is really none about it) and if you think the White Crest is difficult, Well the Black Crested White Polish is something else... But I will also be posting about them here.

 

[Amer]

I've done an extensive research on the matter and will be posting my take on the matter(with very little research to back it up since there is really none about it) and if you think the White Crest is difficult, Well the Black Crested White Polish is something else... But I will also be posting about them here.

Ok, thank you!

 

[nicalandia]

I would like to point out that these are my observations and have not been verified by proper genetic research.

I believe that the White Crest color in Polish(as in White Crested Black Polish and the White Crested Red Polish) is independant of e allele(can be had in many e allele backgrounds for example Extended Black, Birchen, eb brown), and is not a new mutation of the Cr incompletely dominant crest mutation.

I believe that what gives the White Color to the crest is an allelic mutation of the Mottling m allele, it's recessive in nature(recessive to Mo+) and I propose the gene symbol m^wc caused by an Endothelin Receptor B2 (EDNRB2) mutation, recently a Japanese team of research was able to identify and new mottling m allle mutation that is responsible for the white color of the Minohiki Japanase breed, they have assigned to that new mutation a gene symbol mo^w(for recessive mottling White Pattern), when they cross mo^w/mo^w parent with recessive mottling mo/mo parent the result shows a Mottling like pattern(looks very much like exchequer pattern)

Here is a recap of the research done by my friend Sigrid(she did the recap but the research was done by a Japanese team) http://www.chickencolours.com/New mottled allele.pdf and the research team work: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0086361

So the Mottling m allele seem to be prone to allelic mutations(just like dominant white i+,I, I^D, I^S), so far only two have been properly documented but I believe there are at least 5 mutations(Mo+, mo, mo^w, mo^wc, mo^e, the last is for the exchequer pattern that used to be called pied but research has atleast confirm that it is the same or allelic to mottling), I believe that genetic mapping of these patterns(White Crest and Exchequer) need to be done to properly identify these mutations.

WC Polish chicks display a mottled like chick down( White Head and white feather tips like Tolbunt Polish before they moult to adult feathers)

I believe that the cross of Mottled Polish with WC Polish will produce intermediate pattern(very small amount of mottling on the F1) and due to the allelic nature of mo^wc one can't have a full mottled polish with a full White Crest.

The feathersite has this hen posted as white Crested Mottled, but I believe that this he is actually mo/mo^wc F1 cross

 

[nicalandia]

I have not seen the WC Polish SOP yet(been trying to find it to read it), but I believe that when breeding for WC small white spots on the body resembling scarce mottling should be bred against it.

Here is a picture of WC Dun/Chocolate Polish showing such pattern.

I believe that if bred for mo^wc/mo^wc the mottling on the body could be enhanced

 

[nicalandia]

I was able to find out that some breeders in Holland are already doing that.

Here is a picture of them, they are called Black and White White Crested
https://www.kippenpagina.nl/kippenrassen/hollandskuifhoenkrielen.html

 

[Amer]

I would like to point out that these are my observations and have not been verified by proper genetic research.

I believe that the White Crest color in Polish(as in White Crested Black Polish and the White Crested Red Polish) is independant of e allele(can be had in many e allele backgrounds for example Extended Black, Birchen, eb brown), and is not a new mutation of the Cr incompletely dominant crest mutation.

I believe that what gives the White Color to the crest is an allelic mutation of the Mottling m allele, it's recessive in nature(recessive to Mo+) and I propose the gene symbol m^wc caused by an Endothelin Receptor B2 (EDNRB2) mutation, recently a Japanese team of research was able to identify and new mottling m allle mutation that is responsible for the white color of the Minohiki Japanase breed, they have assigned to that new mutation a gene symbol mo^w(for recessive mottling White Pattern), when they cross mo^w/mo^w parent with recessive mottling mo/mo parent the result shows a Mottling like pattern(looks very much like exchequer pattern)

Here is a recap of the research done by my friend Sigrid(she did the recap but the research was done by a Japanese team) http://www.chickencolours.com/New mottled allele.pdf and the research team work: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0086361

So the Mottling m allele seem to be prone to allelic mutations(just like dominant white i+,I, I^D, I^S), so far only two have been properly documented but I believe there are at least 5 mutations(Mo+, mo, mo^w, mo^wc, mo^e, the last is for the exchequer pattern that used to be called pied but research has atleast confirm that it is the same or allelic to mottling), I believe that genetic mapping of these patterns(White Crest and Exchequer) need to be done to properly identify these mutations.

WC Polish chicks display a mottled like chick down( White Head and white feather tips like Tolbunt Polish before they moult to adult feathers)View attachment 1903439



I believe that the cross of Mottled Polish with WC Polish will produce intermediate pattern(very small amount of mottling on the F1) and due to the allelic nature of mo^wc one can't have a full mottled polish with a full White Crest.

The feathersite has this hen posted as white Crested Mottled, but I believe that this he is actually mo/mo^wc F1 cross

I have not seen the WC Polish SOP yet(been trying to find it to read it), but I believe that when breeding for WC small white spots on the body resembling scarce mottling should be bred against it.

Here is a picture of WC Dun/Chocolate Polish showing such pattern.

View attachment 1903487


I believe that if bred for mo^wc/mo^wc the mottling on the body could be enhanced

I was able to find out that some breeders in Holland are already doing that.

Here is a picture of them, they are called Black and White White Crested
https://www.kippenpagina.nl/kippenrassen/hollandskuifhoenkrielen.html

View attachment 1903509

Wow! Thank you! I am surprised that I actually understand all that!
mo^wc is proposed to be a mutation of the mottling allele. I noticed as well that it seems to mutate more than people realize. Before you even showed the chick down example I made the connection of down color. I can see how it would make spotting throughout the body.
I believe that you have a good theory backed with solid evidence and I totally agree with you.

 

[nicalandia]

mo^wc is proposed to be a mutation of the mottling allele. I noticed as well that it seems to mutate more than people realize. Before you even showed the chick down example I made the connection of down color. I can see how it would make spotting throughout the body.
I believe that you have a good theory backed with solid evidence and I totally agree with you.

Thanks, I was about to post that I arrived to that conclusion by process of elimination.

The White Crest Dilution mutation is not:

Related to Sex linked Gold/Silver/Sex linked sex-linked imperfect albinism
Related to Sex linked Dilution mutations like Chocolate or Sex linked Dilution B^Sd,B^Esd

Related to Autosomal Dominant White and it's many allelic mutation(I,I^D,I^S)
Related to Autosomal Blue/Splash/RSY Dilution RSY~D
Related to Autosomal Lavender

So what could cause the dilution in both Chick and Adult feathering? It has to be form of mottling(Black Crested Polish chicks have black heads since the hatch)

 

[Cyprus]

I have not seen the WC Polish SOP yet(been trying to find it to read it), but I believe that when breeding for WC small white spots on the body resembling scarce mottling should be bred against it.

Here is a picture of WC Dun/Chocolate Polish showing such pattern.

View attachment 1903487


I believe that if bred for mo^wc/mo^wc the mottling on the body could be enhanced

I can get you that SOP sometime soonish if you want it.