FINE-MAPPING MILK PRODUCTION QTL ON BTA6: ANALYSIS OF THE BOVINE OSTEOPONTIN GENE

Authors: SCHNABEL, ROBERT - UNIVERSITY OF MISSOURI; ASHWELL, MELISSA - NORTH CAROLINA STATE UNIV; Sonstegard, Tad; Connor, Erin; Van Tassell, Curtis - Curt; KIM, JONG-JOO - UNIVERSITY OF ARIZONA; TAYLOR, JEREMY - UNIVERSITY OF MISSOURI

Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/20/2004
Publication Date: 1/14/2005
Citation: Schnabel, R.D., Ashwell, M.S., Sonstegard, T.S., Connor, E.E., Van Tassell, C.P., Kim, J., Taylor, J.F. 2005. Fine-mapping milk production qtl on bta6: analysis of the bovine osteopont [abstract]. Plant and Animal Genome XIII. p. 532.

Interpretive Summary: THIS IS AN ABSTRACT ONLY. NO INTERPRETIVE SUMMARY REQUIRED.

Technical Abstract: BTA6 harbors multiple QTL affecting milk production traits in dairy cattle. In order to fine-map these QTL, 3317 bulls comprising 45 half-sib families were genotyped for 38 markers. The data were analyzed using least squares regression (QTL Express), linkage disequilibrium (LDVCM) and full pedigree MCMC (LOKI) methods. A total of 19 sires were segregating for at least one QTL under a half-sib model at chromosome-wide P<0.05. LD results across families indicated the presence of up to 7 QTL (3 within a 6cM region) whereas LOKI revealed only 3 QTL. Positional/functional candidate genes have been identified for five of the QTL. Osteopontin (OPN or SPP1) is a strong candidate for the QTL near marker BM143. The entire OPN gene and 5kb upstream was sequenced from four segregating sires and four non-segregating sires (12.3kb per animal). A total of 15 SNPs were identified but only one SNP resulted in sire genotypes that were concordant with the segregation status of all eight sires.