Which Rata doméstica breeds come in Bareback?

Club breed standards describe Bareback for the Rata Doméstica.

Rata doméstica pattern

Bareback

Rat marking: a colored hood over the head, neck and shoulders with no stripe down the back, the rest white (AFRMA Bareback, NFRS provisional).

1 Rata doméstica breed lists Bareback. It is in a club standard for 1 breed.

Breed	AFRMA	NFRS
Rata Doméstica	Estándar (“Bareback”)	Alternativo (“Bareback (provisional)”)