An advanced sheep (Ovis aries, 2n = 54) cytogenetic map and assignment of 88 new autosomal loci by fluorescence in situ hybridization and R‐banding

Abstract

SummaryPresented herein is an updated sheep cytogenetic map that contains 452 loci (291 type I and 161 type II) assigned to specific chromosome bands or regions on standard R-banded ideograms. This map, which significantly extends our knowledge of the physical organization of the ovine genome, includes new assignments for 88 autosomal loci, including 74 type I loci (known genes) and 14 type II loci (SSRs/microsatellite marker/STSs), by FISHmapping and R-banding. Comparison of the ovine map to the cattle and goat cytogenetic maps showed that common loci were located within homologous chromosomes and chromosome bands, confirming the high level of conservation of autosomes among ruminant species. Eleven loci that were FISH-mapped in sheep (B3GAT2, ASCC3, RARSL, BRD2, POLR1C, PPP2R5D, TNRC5, BAT2, BAT4, CDC5L and OLA-DRA) are unassigned in cattle and goat. Eleven other loci (D3S32, D1S86, BMS2621, SFXN5, D5S3, D5S68, CSKB1, D7S49, D9S15, D9S55 and D29S35) were assigned to specific ovine chromosome (OAR) bands but have only been assigned to chromosomes in cattle and goat.

Quantitative trait loci for resistance to infection in sheep using a live Salmonella Abortusovis vaccine

“…The OAR21 QTL for bacteria per gram in the left lymph node and for the cumulated number of bacteria per gram in both left and right nodes are located at similar positions and overlap with loci encoding IL‐4 and IL‐5 (36 cM), which are involved in the Th2 type immune response (Di Meo et al. 2007).…”