DNA Testing – Rose Comb

Rose Comb (R) DNA Test

This test detects the presence or absence of the Rose Comb (R) gene in chickens.

The rose comb gene is a dominant mutation. Birds that carry at least one copy of R will express a rose-type comb unless another comb-modifying gene alters its appearance. Birds that do not carry the R gene remain on a single (straight) comb genetic background, provided no other comb modifiers are present.

This test is used to determine whether a bird:

• Carries the Rose Comb (R) gene (One or Two Copies)

• Does not carry the Rose Comb (R) gene

How this applies to walnut combs (including Silkies)

A walnut comb is produced by the combined presence of two dominant genes:

• Rose comb (R)

• Pea comb (P)

A bird must carry at least one copy of both genes to express a walnut comb. If either gene is absent, the walnut comb will not form.

Walnut-combed birds, including Silkies, may visually appear uniform, but they can still lack the Rose Comb (R) gene in certain breeding outcomes depending on how the genes segregate. When walnut-combed birds are paired, offspring that do not inherit the Rose Comb gene will develop single (straight) combs.

This test allows breeders to:

• Confirm whether a walnut-combed bird carries the Rose Comb (R) gene

• Identify breeders capable of producing single-comb offspring

• Make informed pairing decisions before breeding