Defining and Mapping Mammalian Coat Pattern Genes: Multiple Genomic Regions Implicated in Domestic Cat Stripes and Spots

Abstract

Mammalian coat patterns (e.g., spots, stripes) are hypothesized to play important roles in camouflage and other relevant processes, yet the genetic and developmental bases for these phenotypes are completely unknown. The domestic cat, with its diversity of coat patterns, is an excellent model organism to investigate these phenomena. We have established three independent pedigrees to map the four recognized pattern variants classically considered to be specified by a single locus, Tabby; in order of dominance, these are the unpatterned agouti form called ''Abyssinian'' or ''ticked'' (T . We demonstrate that at least three different loci control the coat markings of the domestic cat. One locus, responsible for the Abyssinian form (herein termed the Ticked locus), maps to an 3.8-Mb region on cat chromosome B1. A second locus controls the Tabby alleles T M and t b , and maps to an 5-Mb genomic region on cat chromosome A1. One or more additional loci act as modifiers and create a spotted coat by altering mackerel stripes. On the basis of our results and associated observations, we hypothesize that mammalian patterned coats are formed by two distinct processes: a spatially oriented developmental mechanism that lays down a species-specific pattern of skin cell differentiation and a pigmentation-oriented mechanism that uses information from the preestablished pattern to regulate the synthesis of melanin profiles.

Coat genetic markers of the domestic cat Felis catus (Felidae) from southwestern Colombia

“…La nomenclatura genética utilizada sigue la propuesta por el Committee on Standardized Genetic Nomenclature for Cats (12) a excepción del mapeo de las posiciones cromosómicas que configuran los patrones Tabby para el cual se sigue a Eizirik et al 2010 (13). Los genes utilizados para el inventario genético de las poblaciones se indican en la tabla 1.…”

“…The genetic nomenclature used follows the Committee on Standardized Genectic Nomenclature for Cats (12) proposal, except for the chromosomic positions that make up the Tabby patterns, for which we followed Eizirik et al (13). The genes used for the genetic inventory of populations are listed in (Table 1).…”

A genome-wide scan study identifies a single nucleotide substitution in ASIP associated with white versus non-white coat-colour variation in sheep (Ovis aries)

“…Nevertheless, until now, without the benefit of sheep whole-genomic data, elucidation of the molecular mechanisms of the ASIP gene regulating coat colour in domestic sheep would need additional efforts. Given that some colour and pattern alleles are known to be penetrant (for example, Eizirik et al, 2010), it would be also interesting to assess the dominant and recessive models of gene actions (for example, dominant and recessive epistasis; complementary or duplicate gene action) among the significant SNPs. However, due to the limited inheritance data among the individuals (for example, individuals from F2 and further generations) in this study (see Li et al, 2011), further genetic segregation investigations on the significant SNPs identified here are necessary for understanding the inheritance of the coat colour and pattern in sheep.…”

Génétique de la couleur et de la texture du pelage chez le chat domestique

“…Ce locus avait été cartographié sur le chromosome B1 du chat . Récemment, l'implication de deux locus épista-tiques pour gouverner ces trois patrons a été démontrée (Eizirik et al 2010 (Eizirik et al 2010).…”