Genome-wide association study for ham weight loss at first salting in Italian Large White pigs: towards the genetic dissection of a key trait for dry-cured ham production

Protected designation of origin dry-cured hams are the most important productions of the Italian heavy pig industry. Hams capable of minimal seasoning losses produce better quality dry-cured hams. Ham weight loss during the first 7 days in brine (first salting) is highly correlated with the total loss of weight up to the end of seasoning, and it has quite high heritability (0.30-0.61). For these reasons, ham weight loss at first salting has been included as a meat quality trait in the Italian heavy pig selection program. In this work, we carried out a genome-wide association study for this parameter in the Italian Large White pig breed by genotyping 1365 animals with the Illumina BeadChip PorcineSNP60 chip. A total of 44 single nucleotide polymorphisms (SNPs) had a P-nominal value below 5.0E-04, five of which were below 5.0E-05 and one of them (ALGA0057985 on chromosome 10) was associated with this trait at a P-Bonferroni threshold of 0.10. These SNPs identified a total of at least 29 putative QTLs that were located on most porcine autosomal chromosomes. This study provides genomic information that could be useful in dissecting this complex trait by identifying potential candidate genes whose function could contribute to understanding the biological mechanisms affecting meat quality for seasoning aptitude.