Data from an F2 cross between the Berkshire and Yorkshire breeds was used to detect and characterize chromosomal regions (quantitative trait loci, QTL) that affect growth, composition, and meat quality traits. A new method of analysis was used that combines the power of the line-cross model to detect QTL that differ between the breeds and the half-sib model to detect QTL that segregate within the breeds. The complementary information that is capitalized on in the combined models increased the number of QTL detected and allowed characterization of the detected QTL in terms of their segregation within the original breeds. This provides valuable information for subsequent QTL analyses and marker-assisted breeding schemes.