Charcoal

Allele symbol cha or Cha.

Status

Well accepted and documented. But its role in chicken colors remains unclear. There may exist dominant and recessive alleles.

Sexlinked or autosomal?

Autosomal. Chromosomally linked to O and P.

Degree of dominance

Incomplete recessive^Henk69; see also Heterozygosity.

Phenotypic effect

Boosts eumelanin expression eg on (upper) hackle. Important, but not exclusive, factor to create solid eumelanin chickens, especially roosters.

chick down

Probably noticeable as darkened, but not always. Columbian may cause dramatic change in expression eg. compare quail d'anver and wildfarbig german bantam.

rooster

On its own not very conspicuous. But generally darker.

hen

Strong expression on hackle, little when heterozygous (back of the head).

Heterozygosity

The stronger a melanizer the e-locus base of the chicken is, the more powerful are the effects of (one dose of) charcoal.

Epistatics

May be boosted when combined with Columbian eg Lakenvelder.

Role in certain complex phenotypes

• an incomplete lacing effect likw Ml
• may be the hackle melanizer in Lakenvelder combined with Co
• may help in wheaten based double laced
• may occur in Quail
• Self/solid