FAQ: In the BVA-International nomenclature, the name of a mutation is never written with a capital letter (except at the start of a sentence.) That seems illogical to me because in our language experience, the name of a mutation is a proper noun. So a noun that names a person or thing as an individual, something unique. In most cases, proper nouns are capitalized. So why not in names for color mutations?
You are right that the name of a colour mutation in Dutch is always written without a capital: dominant pied, opaline, turquoise, etc. But each language has its own guidelines about this; in Australia, for example, the names for color mutations are always written with a capital letter and there is nothing wrong with that. The use of capital letters for names in color mutations, therefore, depends on local grammar.
This is also mentioned in the international guidelines: “The name of a colour mutation in Dutch is always written without a capital: dominant pied, opaline, turquoise, etc. Except at the start of a sentence or in another context in which a capital is appropriate. This can differ between countries and depends on the local grammar.“