Skin color is recessive, dominant, and sex-linked respectively.
Yellow skin is recessive (w)
White skin, wild type, is dominant (W)
Dermal Melanin, or black skin, is sex-linked, recessive and wildtype (id+) the absence of dermal melanin is dominant (Id)
CQ's are RIR and RI White crosses, which gives them homozygous recessive yellow skin (w)
Turkens and D'Uccles have white skin (W)
Silkies have the recessive dermal melanin (id+)
Dermal Melanin is sex-linked. Roosters have two copies and hens have 1. It takes two copies in males to exhibit the gene and one in females to exhibit the gene.
When a Silkie rooster carrying two copies of id+ is crossed with a CQ hen carrying one copy of w the male offspring inherit one copy of w from their mother and one copy of id+ from their father. Since they do not have both recessive copies of id+ they exhibit yellow skin.
The female offspring only inherit one copy of id+ from their father thus causing them to exhibit dark skin.
When a Silkie rooster is crossed with a Turken hen the male offspring inherit one dominant W from their mother and one recessive id+ from their father, therefore exhibiting white skin. The females, who inherit only one recessive copy of id+ from their father exhibit dark skin.
When a D'Uccle rooster carrying two dominant copies of W is crossed with an EE hen the resulting offspring will all have white skin as each offspring will inherit one copy of dominant W which will turn all skin white.