Contrasts between p-values (log
scale) obtained for interval mapping tests within progeny with LW paternal alleles and within progeny with MS paternal alleles on the PorQTL pedigree. Interval mapping tests were applied on SSC2 (y-axis, 40-70 cM region) with all available positions in the genome scan as candidate for interaction (x-axis, from SSC1 to SSC18 (SSC2 being excluded)). A blue (orange) spot indicates that the SSC2 QTL is more likely to be detected in progeny that inherited the Large White (Meishan) allele paternally at the candidate position for interaction. Extreme colors indicate the highest p-value differences, i.e. the strongest candidates for interaction with the SSC2 QTL.