An integrated radiation hybrid map of bovine chromosome 19 and ordered comparative mapping with human chromosome 17.

We recently constructed a 5000-rad cattle whole-genome radiation hybrid panel with the primary objective of integrating linkage maps of microsatellites with evolutionarily conserved genes into one ordered map. This study utilized the panel to construct a radiation hybrid (RH) map of bovine chromosome 19 (BTA19). Twelve microsatellites from different cattle linkage maps, 15 coding genes, and 2 expressed sequence tags were placed on the BTA19 RH map, with 16 of the markers ordered with odds of at least 1000:1. When the BTA19 RH map was compared with human chromosome 17 cytogenetic and RH maps, rearrangements in linear order were revealed for homologous genes on these two chromosomes that are totally conserved at the level of synteny mapping. Radiation hybrids, which have to date been used almost exclusively in mapping the human genome, are a potentially powerful resource for constructing maps for other species and for ordered comparative mapping between species.