ABSTRACT
The chicken gene map has been under development since 1902, and a number of updates have been published since 1936. The majority of loci that have been assigned to linkage groups code for morphological traits, but some biochemical loci have been mapped. The most extensive chromosome maps are of the Z (sex) chromosome and chromosome 1. A few loci have been assigned to chromosomes 2, 6, and 17, and there are three major linkage groups that have yet to be assigned to a chromosome. Each of these known linkage groups and chromosome maps is discussed in this review. New technologies are identifying more loci, and these technologies have great promise for increasing our knowledge of the genetic maps of all avian species. The improved map will be of benefit to commercial breeders, avian genetic researchers, and other members of the biological research community.
