Identification of QTL for production traits in chickens

Christiane Hansen1, Nengjun Yi, Yuan Ming Zhang

  • 1USDA, ARS, Avian Disease and Oncology Laboratory, East Lansing, Michigan, USA.

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In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
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Overview
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Polygenic Traits

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