|Freking, Bradley - Brad|
Submitted to: International Conference on Animal Genetics
Publication Type: Abstract Only
Publication Acceptance Date: 7/1/1998
Publication Date: N/A
Technical Abstract: The muscling loci callipyge (CLPG) and Carwell have been mapped to the telomeric region of sheep chromosome 18 (OAR18). Therefore, further detailed linkage mapping has been undertaken to facilitate finer resolution mapping in the vicinity of the CLPG and Carwell loci. Linkages between marker loci were analysed in the AgResearch International Mapping Flock (IMF) and 303 progeny from the Carwell breeding flock of Landcorp Farming Ltd. Genotypes from 28 markers, of which 16 (14 microsatellite loci, one gene polymorphism (IGHE) and one VNTR locus) were additional to the OAR18 linkage map of de Gortari et al. (1998, Mamm. Genome 9, 204), have been scored in the IMF. Genotypes for 9 informative microsatellite loci spanning the distal region of OAR18 were scored in the Landcorp flock. Linkage maps were constructed and verified using the CRI-MAP software and genetic distances were estimated using the Kosambi mapping function. Sixteen marker loci were ordered with another three microsatellite loci showing no recombination with ordered loci. The sex-averaged linkage map spanned 107 cM from BMS1117 to VNTR16 which extended the de Gortari et al. OAR18 map beyond BM3413 and BMS1561. The male and female map lengths were 110 cM and 103 cM, respectively. Genetic distances between marker loci were similar between the two OAR18 maps, except the distance between CSSM18 and BMS1561 in the de Gortari et al. map appeared greater than the distance between CSSM18 and OY5 in the present map (14 cM and 3 cM, respectively). OY5 was isolated from a sheep YAC clone containing BMS1561. The mapping of PIA and IGHE to the distal portion of OAR18 defined regions on HSA14q and MMU12 as equivalent for comparative gene analysis.