Cat coat genetics as "transmembrane aminopeptidase Q" ("Taqpep"), which also produces the king cheetah coat variant. Spotted tabbies have their stripes broken up into spots, which may be arranged vertically or horizontally. A 2010 study suggests that spotted is caused by the modification of mackerel stripes, and may cause varying phenotypes such as "broken mackerel" tabbies via multiple loci. The "Ticked" gene, "T / t", produces an "Abyssinian ticked" or non-patterned agouti tabby with the dominant allele, having virtually no stripes or bars. Stripes usually remain to some extent on the face, tail, legs, and sometimes the chest. The dominant ticked tabby allele
Mackerel 21 species in all—18 of those are classified into the genus "Scomberomorus", two into "Grammatorcynus", and a single species into the monotypic genus "Acanthocybium". In addition, a number of species with mackerel-like characteristics in the families Carangidae, Hexagrammidae and Gempylidae are commonly referred to as mackerel. There has been some confusion between the Pacific jack mackerel ("Trachurus symmetricus") and the heavily harvested Chilean jack mackerel ("Trachurus murphyi"). These have been thought at times to be the same species, but are now recognised as separate species. The term "mackerel" is also used as a modifier in the common names of other