They are homozygous for the dominant SB1 allele at the Sabino 1 locus, which has been mapped to KIT. Sabino-white was one of the earliest dominant white alleles discovered, but was not originally recognized as such, hence the different name.
They are homozygous for the dominant white allele at the Sabino 1 locus, which has been mapped to KIT. The Sabino-white was one of the earliest discovered dominant white alleles, but it wasn't initially recognized as such, hence its different name.