Articles about American Pit Bull Terrier
...to start reading this article from the beginning please click on here...It is dominant over the extension (E) allele. In our breed, interactions with alleles at the B and D loci produce a rich variety of brindle colors: Ay-B-D-Ebr- black brindle Ay-B-ddEbr- blue brindle Ay-bbD-Ebr- brown or chocolate brindle Ay-bbddEbr- fawn brindle (The (-) as the second allele at the locus pair denotes an allele that is uncertain because of the dominant nature of the first allele. It could be homozygous or heterozygous with any of the other alleles.) (E) - EXTENSION: The E allele produces normal extension or expression of dark pigment. It interacts with Locus A alleles to produce a variety of effects: As-E-black/brown Ay-E-red or buckskin with or without black ticked hairs (on head and back) referred to as sable in other breeds (ee) - RESTRICTION: The homozygous (ee) alleles restricts the expression of dark pigment, producing the yellow shades by light pigment. It does allow the expression of dark pigment on the nose, lips and eye rims. It is recessive to all other alleles in the E series. Homozygous (ee) alleles interferes with the expression of most Locus A alleles. As-ee buckskin Ay-ee light tan Locus G pair: Progressive Graying (g) uniform color throughout life Research concludes that the AST breed are homozygous (gg) with dogs retaining their coloring throughout their lifetime. The G dominant allele present in other breeds produces a silvering or graying of the coat over time and the recessive (g) allele, giving a uniform color throughout the dogs lifetime. Locus M Pair: Merle Pattern (m) uniform pigment Research has shown that our breed has only the recessive (m) allele at this locus. The homozygous recessive (mm) produces a uniform pigment in the breed. The (M) dominant allele produces the merle or dapple pattern. The dominant (M) allele has been identified in Collies, Shetland sheepdogs, Australian Shepherds, Cardigan Welsh Corgis, Great Danes, Louisiana Catalhoula, Spotted Leopard Dogs and Dachshunds.
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