LOCALIZATION OF THE U2 LINKAGE GROUP OF HORSES TO ECA-3 USING CHROMOSOME PAINTING

The U2 linkage group of horses includes the genes albumin (ALE), vitam in D binding protein (GC), mitochondrial glutamate oxaloacetate transa minase 2 (GOT2), and haptoglobin (HP) which are found on two human chr omosomes, namely, 4 (HSA 4) and 16 (HSA 16). Likewise these genes are also found on two different chromosomes in mice, rats, and cattle. Chr omosome painting demonstrated that only horse chromosome 3 (EGA 3) hyb ridized with whole chromosome paints for both HSA 4 and HSA 16. This i ndicated that the equine U2 linkage group occurs on ECA 3, spanning th e centromere. This technique will be useful to study the chromosome re arrangements associated with speciation of the genus Equus.