DNA Testing – Frizzle Feather Gene

Frizzle Gene Test (KRT75)

This DNA test detects the presence of the Frizzle gene, a mutation in the KRT75 gene responsible for producing curled or “frizzled” feathers in chickens. Birds that carry this gene show varying degrees of feather curling, depending on whether they inherit one or two copies.

The Frizzle gene is incompletely dominant, meaning its expression changes depending on zygosity:

• Birds with one copy of the gene (F/f) typically show classic frizzled feathering—feathers that curl outward.

• Birds with two copies (F/F) often show brittle, sparse, or over-curled feathers and are sometimes referred to as frazzles. These birds can have associated health issues, making them unsuitable for breeding.

• Birds with no copies (f/f) will not show frizzling and pass on only straight-feathered genetics.

This test allows you to determine whether your bird carries the Frizzle gene and how many copies it has. It is especially valuable for breeders looking to safely produce frizzled offspring without unintentionally creating frazzled birds.