In other species: Tasmanian devil , common brushtail possum , gray wolf , coyote , dog , red fox , domestic cat , ass (donkey) , horse , pig , Arabian camel , llama , Western roe deer , impala , taurine cattle , goat , sheep , rabbit , tassel-eared squirrel , North American deer mouse , Mongolian gerbil , meadow voles , domestic guinea pig , fallow deer , alpaca , leopard cat , oldfield mouse , Kodkod , Colocolo , Asiatic golden cat , Northern mole vole , Eurasian water mole

Categories: Pigmentation phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 611742 (trait) , 600201 (gene)

Single-gene trait/disorder: yes

Mode of inheritance: Autosomal recessive

Disease-related: no

Key variant known: yes

Year key variant first reported: 2012

Cross-species summary: This locus, ASIP, encodes the agouti signalling protein, a peptide antagonist of the melanocyte-stimulating hormone receptor (MC1R), which is the product of the extension locus. As explained by Schneider et al. (PLoS Genet 10(2): e1004892; 2015), "The most common causes of melanism (black coat) mutations are gain-of-function alterations in MC1R, or loss-of function alterations in ASIP, which encodes Agouti signaling protein, a paracrine signaling molecule that inhibits MC1R signaling".

Inheritance: Robinson (1969, 1970) provided evidence of autosomal recessive inheritance of the melanistic phenotype, based on the breeding records of 439 animals.

Molecular basis: By sequencing the candidate gene ASIP in "wild-type" non-melanistic leopards and melanistic leopards ("black panthers"), Schneider et al. (2012) showed that the "black panther" phenotype is due to a "non-synonymous mutation located in exon 4 (C333A) predicted to introduce a stop codon at amino acid position 111. All 11 analyzed melanistic leopards . . . were homozygous for this mutation, while the wild-type individuals (i.e. bearing a yellowish background coloration with black rosettes; . . .) were either homozygous for the ancestral ‘A’ allele or heterozygous." Sooriyabandara et al. (2023) "used reference-based assembled nuclear genomes of Sri Lankan wild type and melanistic leopards and de novo assembled mitogenomes ... . ... [The authors] identified a single nucleotide polymorphism in exon-4 Sri Lankan melanistic leopard, which may completely ablate Agouti Signalling Protein (ASIP) function. The wild type leopards in Sri Lanka did not carry this mutation, suggesting the cause for the occurrence of melanistic leopords in the population."

Associated gene: