A genetic map of nine loci on bovine Chromosome 2

A male-specific genetic linkage map of nine loci on bovine Chromosome (Chr) 2 (BTA2) was constructed from 306 offspring belonging to six paternal halfsib families. Loci studied were the structural genes for liver/bone/kidney alkaline phosphatase (ALPL), Gardner-Rasheed feline sarcoma (v-fgr) oncogene homolog (FGR), alpha-L-fucosidase 1 (FUCA1), and fibronectin 1 (FN1), and the microsatellite loci ARO28, DU17S2, DU17S3, DU17S4, and DU17S5. Genotyping was performed by restriction fragment length polymorphism (RFLP) for structural genes and polymerase chain reaction (PCR) for the microsatellites. Two genetically independent linkage groups were identified. The order of genes in the first linkage group, L31, is (ARO28-FN1)-FGR-FUCA1-ALPL, covering a map distance of 34.1 cM between terminal markers. The second linkage group, L32, consists of DU17S2-DU17S5-DU17S4-DU17S3 and is 41.3 cM in length. Genetic linkage between FN1 and FGR confirms previous physical assignment of these genes to the same synteny group. Currently, the genetic linkage of FN1 and FGR is unique to cattle and thus localizes a site of chromosomal evolution to a 22-cM interval between the two loci.