Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: February 15, 2001
Publication Date: June 20, 2001
Citation: McCoard, S.A., Fahrenkrug, S.C., Freking, B.A., Rohrer, G.A., Wise, T.H., Ford, J.J. 2001. Comparative mapping of the porcine x chromosome [abstract]. Journal of Animal Science. 79 (Supplement 2):36. (Abstract #23) Technical Abstract: Porcine chromosome X (SSCX) harbors QTL responsible for testicular size and elevated FSH levels. Testicular size establishes the upper limit for total daily sperm production and thereby affects financial returns of boar studs. These QTL were identified using primarily anonymous microsatellite markers that give little insight into the identification of the genetic basis of these phenotypes. In order to take maximal advantage of human- pig comparative mapping strategies for positional candidate gene cloning, a detailed comparative map employing gene-linked markers is required. Therefore, the objective of this study was to develop an integrated map of SSCX using both microsatellite and gene-linked markers. A physical map of SSCX was constructed using 54 markers typed onto the T43 radiation hybrid (RH) panel, and linked with a LOD of >10 according to RHMAPPERv1.22. The markers included 33 microsatellite and 21 gene-linked markers. In addition, 23 gene-linked markers were amplified from the MARC reference population, and found by DNA sequencing to contain single nucleotide polymorphisms (SNPs) suitable for genetic mapping. SNPs were discovered in 20 gene-linked markers, 13 of which were also mapped by RH analysis. Analysis of our integrated comparative map of SSCX supports a striking conservation of synteny between SSCX and HSAX. This integrated map will be valuable for the selection of candidate genes for pig reproductive QTL mapped to the porcine X chromosome.