Carbon Pattern 2 (Bengal)

The `charcoal` coloration pattern in the Bengal breed is a distinctive phenotype unique to this breed. This pattern is characterized by a dark facial mask and an equally dark dorsal band.

Definition

The charcoal coloration pattern refers to a pattern defined by the combination of a thick dorsal band and a dark facial mask on a lighter background, creating a noticeable contrast. This color distribution is determined by the Agouti (ASIP) gene, which produces a regulatory protein for the distribution of eumelanin (black pigment). A variant of this gene causes increased eumelanin production in specific areas of the coat.

Genetic basis

The `charcoal` pattern is the result of compound heterozygosis, i.e. the combination of one copy of two different genetic variants. This coloration pattern appears to be the result of one copy of the agouti allele (Apbe) from the leopard cat and one copy of the non-agouti allele from the domestic cat (a). The mode of inheritance is estimated to be autosomal dominant, although the Apbe allele is not completely dominant over a, as both are required to express the charcoal phenotype. In this case, we studied the c.41G>C variant, which involves a single nucleotide change in the ASIP gene, resulting in increased production of eumelanin (black pigment) in specific areas of the coat. It is important to note that the final expression of this phenotype may depend on interaction with variants at other loci, such as B and K, which also affect the coloration and pattern of the coat.

Other relevant information

The ASIP gene shows a different interaction when present in domestic cats compared to Asian leopard cats, which is known as genomic incompatibility. In Asian leopard cats, the ASIP gene does not cause charcoal coloration; however, in domestic cats, this same gene does cause charcoal coloration.

Bibliography

Gershony LC, Penedo MCT, Davis BW, et al. Who`s behind that mask and cape? The Asian leopard cat`s Agouti (ASIP) allele likely affects coat color phenotype in the Bengal cat breed. Anim Genet. 2014;45(6):893-897.

Kaelin CB, Xu X, Hong LZ, et al. Specifying and sustaining pigmentation patterns in domestic and wild cats. Science. 2014;346(6215):1313-1317.