It has become increasingly obvious over a period of years that an extremely dark agouti allele is present in the purebred Romeldale/CVM gene pool. It was initially identified as “a very dark self-color (Aa),” but with the passing of time and increased frequency of appearance, it spurred the authors’ attempt to identify the nature of this gene that seemed to darken even the lightest non-white agouti alleles. The frequency of incidence seemed to point to an as-yet-unidentified agouti allele. Through the use of lamb birth photos, the authors have identified the expression of this agouti allele as specific very small white displays on the head and neck of newborn lambs. They have named it Paddington blue (Apbl), since in many ways its behavior is similar to the dark blue allele (Adbl) also found at this locus. In addition to its own white display, Apbl is strong enough to darken the white display of the agouti allele with which it is paired. Research continues, as an age-related darkening effect seems to be connected to the presence of this allele.