The linkage map of Sus scrofa chromosome 5 (SSC5) (http://www.thearkdb.org) ranges in length from 114.4 cM (USDA-MARC.2 with 45 loci, Rohrer et al. 1996) to 176.0 cM (PiGMaP.1.5 with 14 loci, Zhang et al. 1995). To date, quantitative trait loci (QTLs) have been found on SSC5 by Knott et al. (1998), Rohrer and Keele (1998), Bidanel et al. (2001) and Malek et al. (2001a) for back fat thickness; by Malek et al. (2001b) and De´saute´ s et al. (2002) for stress response traits; by Malek et al. (2001b) for muscle light reflectance, by Wilkie et al. (1999) for uterine length and by Cassady et al. (2001) for the number of stillborn piglets.