Blue with dark areas?

[AOrchard]

What is going on with this lady's genetics that her body looks blue with darker feathers/areas? Is it normal for blues to be so irregularly colored? If so, is this a modifying gene, or something she'll grow out of like the occasional white feather in some blacks? I understand that dark edging on blues indicates they carry the pattern gene, but that doesn't seem to explain the dark splotches.

She's a sunnyside rainbow egger, so limited clues there, going on 5 months. In her same batch I did get black, splash, and white laced gray (she looks decidedly blue compared to the gray), along with lots of red based ones (some in background of photos).

 

[JacinLarkwell]

@The Moonshiner might know. I would think it's just a bad blue

 

[OhZark Biddies]

What is going on with this lady's genetics that her body looks blue with darker feathers/areas? Is it normal for blues to be so irregularly colored? If so, is this a modifying gene, or something she'll grow out of like the occasional white feather in some blacks? I understand that dark edging on blues indicates they carry the pattern gene, but that doesn't seem to explain the dark splotches.

She's a sunnyside rainbow egger, so limited clues there, going on 5 months. In her same batch I did get black, splash, and white laced gray (she looks decidedly blue compared to the gray), along with lots of red based ones (some in background of photos).

Here is my understanding of it...

there are three basics genes that make up nice clear single lacing, these are columbian, pattern, and melanotic ( Co, Pg, Ml) ... these are closely linked due to their location of the chromosomes and tend to be inherited as a group...

but to have the most clear single lacing on the feathers the bird would need to be homozygous for all three genes, meaning it carries two copies of each of these three genes...

but when we create crosses of nicely single laced birds to birds with another pattern (maybe like pencil lacing )... then the resulting bird might have only inherited one copy of one or more of these three genes that are involved in making perfect single lacing...

so the result is imperfect lacing, or splotches as in your example bird which is some sort of secret cross created by a specific hatchery

In reality there is likely even more to it than that genetically speaking, but that’s a simplified version of it

 

[Amer]

Simply stated, the blue pattern is usually very uneven. Unless you breed for birds with even coloring, a lot of your blue fowl will look like that.

 

[AOrchard]

Here is my understanding of it...

there are three basics genes that make up nice clear single lacing, these are columbian, pattern, and melanotic ( Co, Pg, Ml) ... these are closely linked due to their location of the chromosomes and tend to be inherited as a group...

but to have the most clear single lacing on the feathers the bird would need to be homozygous for all three genes, meaning it carries two copies of each of these three genes...

but when we create crosses of nicely single laced birds to birds with another pattern (maybe like pencil lacing )... then the resulting bird might have only inherited one copy of one or more of these three genes that are involved in making perfect single lacing...

so the result is imperfect lacing, or splotches as in your example bird which is some sort of secret cross created by a specific hatchery

In reality there is likely even more to it than that genetically speaking, but that’s a simplified version of it.

Okay that makes sense. So some kind of incomplete dominance situation, theoretically due to having one "triple" homozygous laced parent and one with some other pattern. Thanks!

 

[OhZark Biddies]

Okay that makes sense. So some kind of incomplete dominance situation, theoretically due to having one "triple" homozygous laced parent and one with some other pattern. Thanks!

I think that’s the easiest way to think about it, but in reality there are several things going on in addition to but related to the pattern gene group...

it gets past my understanding pretty quickly, but there are unidentified diluting and darkening genes thought to be at play with the pattern genes and color changing genes...

which would be why it can take some time to get clean and consistent lacing, even when working with good looking laced parents... as well as even blue coloring like Amer mentioned...

and then when you start mixing base colors such as a bird that is heterozygous for wheaten and duck wing (eWh/e+) you can start getting results where the dominant gene produces colors oneway when a melanizing protein is acting on an area, but a different way when the protein is not present in another area...

confused? Me too, Lol... I don’t think anyone really understands all those interactions well enough to predict or explain them exactly, once the mixing of too many variables gets involved...

I’ve produced some blue barn yard mixes that look similar to your hen, and spent some time reading about what all is involved... but a lot of it is thought to be caused by genes that are “known but not identified”

 

[AOrchard]

This is super helpful!! Thanks @OhZark Biddies.

 

[NatJ]

Here is my understanding of it...

there are three basics genes that make up nice clear single lacing, these are columbian, pattern, and melanotic ( Co, Pg, Ml) ... these are closely linked due to their location of the chromosomes and tend to be inherited as a group...

Co (Columbian) is not part of the linkage group.

The three that are linked are Pg, Ml, and Db.

Sources for that:
http://www.edelras.nl/chickengenetics/linkages.html
This is a table of gene linkages

https://kippenjungle.nl/kruisingCO.html
This version of the genetics calculator has the option to treat Pg, Ml, Db as linked.

 

[Sally PB]

Whatever she is, she is very pretty.

 

[DarJones]

Be careful with that linkage map. As the guy says, it is obvious it needs updating.

I agree that pattern and melanotic are linked. I am not certain they are on chromosome 1. The reason is because oocyanin (blue egg) is proven on chromosome 1 and yet I have been easily able to select blue egg layers combined with melanotic, pattern, and columbian in my blue egg laying Silver Laced Wyandottes. Either melanotic and pattern are on a different chromosome or else the linkage is VERY easily broken.

As an aside, Whiting Blues have pea comb. Whiting found one bird that had straight comb indicating he had a crossover event that separated pea comb from oocyanin. This would be consistent with a distance between 60 and 80 centimorgans between the genes on chromosome 1. Finding one bird out of thousands raised shows just how rare a crossover can be when the genetic distance on a chromosome is relatively small.