[6][9]: 102  It is recognised in nine European countries: Belgium, Czech Republic, France, Germany, Ireland, Italy, Poland, Slovakia and the United Kingdom.

Frizzled birds are heterozygous for the gene; when two are bred, the offspring inherit the gene in the usual Mendelian 1:2:1 ratio: 50% are heterozygous and frizzled like the parents, 25% have normal feathering, and 25% are "over-frizzled", with brittle feathers resembling pipe-cleaners.

[6] Four colours are recognised in the Entente Européenne standard: black, blue, cuckoo and white.

[4] The Poultry Club of Great Britain recognises nineteen colours for both standard and bantam sizes;[10] not all of them are currently bred.

A deletion that removed part of exon 5 and intron 5 ameliorated the splice site.