Which breed of chicken is recognized as a genetic modification but listed as a breed?

The Frizzle breed is recognized as a genetic modification due to its unique feathering pattern resulting from a specific gene that causes the feathers to curl outward, creating a frizzled appearance. While other breeds like Leghorns, Rhode Island Reds, and Plymouth Rocks have been traditionally bred for certain traits such as egg production or meat quality, they do not possess this specific genetically altered characteristic that defines the Frizzle.

The breeding of Frizzles is considered a genetic alteration rather than a naturally occurring breed standard, making it distinct in the context of recognition as both a breed and a genetic modification. By understanding this context, it's clear why Frizzles hold a unique position in poultry classification and breeding.