Comparisons between positions of loci mapped in sheep on ruminant maps. (Tick marks) Positions of all loci that have been mapped in each species. Dashed and dotted lines are drawn between the same locus on different chromosomes: (dashed) goat–sheep, sheep–MARC97, and MARC97–IBRP97; (dotted) sheep–IBRP97. Lines are drawn only for those loci that have been mapped in sheep. (Although many more links exist between the cattle maps, and additional links can be found when comparing the goat and cattle maps, these are not shown.) The only loci identified by name are those whose relative position differs significantly between maps. All chromosomes are depicted with the centromere at the top except for cattle and goat chromosomes 3, 8, 11, and X for which the order has been inverted. (Box) Region of cattle chromosome 9 that is equivalent to the centomeric portion of sheep and goat chromosomes 14.