Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: April 24, 1997
Publication Date: N/A
Technical Abstract: A genetic map of Ovis aries (haploid N=27) was developed with 514 microsatellite (ms) loci in 26 autosomal linkage groups spanning 3022.3 centimorgans (cM; sex-average) and 102.9 cM (female-specific) of the X chromosome. Genomic conservation among Bovidae allowed the extensive use of ms developed in bovine (397/500 ms, 79.4%) in sheep. Individual linkage groups averaged 19 markers (range 8-48) and 115.8 cM (range 49.0-294.5 cM). The average interval (n=487) between adjacent linked markers was 6.4 cM, with 55.5% of the intervals < 5 cM and only 3.8% of the intervals > 20 cM. Twenty of the 26 autosomes are oriented with respect to the centromere, either directly in sheep or indirectly through orientation on the homologous bovine chromosome. Sixty- six percent (348/500) of the ms on the current sheep map are common on the USDA-ARS cattle map. The common markers span 2866 cM (sex-averaged) in sheep and 2817 cM in cattle or approximately 95% of each genome. Marker order within a linkage group was consistent between the two species with limited exceptions. The previously reported translocation of the telomeric end of BTA9 to BTA14 in sheep (OOV9) (Crawford et al., 1994) is represented by a 15 cM region containing five common markers. The other exceptions involved five independent markers (1.5% of the 348 common markers) from different linkage groups that did not map to the expected homologue linkage group. The high degree of genomic conservation between sheep and cattle will allow us to simultaneously use conserved linkage and physical mapping information while searching for quantitative trait loci (QTL) in both species.