This influences the texture of the dog coat and hair formation. Inheritance (or "options" for coat type) is related to breed. The allele CC is dominant, and results in a curly coat. Only when the dog has two copies of the recessive allele is the coat is of a non-curly type. Some breeds are fixed (only ever curly-coated) for the dominant allele CC. Other breeds can have either curly or non-curly hair. Not to be confused with "curly coat/dry eye" which is a disease.