Association of eight EST-derived SNPs with carcass and meat quality traits in pigs

The identification of genetic markers associated with important economic traits is fundamental to improving the productivity and quality of livestock. In this investigation, we searched for 177 expressed sequence tags (ESTs) putatively involved in meat quality from the available pig EST database, and detected eight single nucleotide polymorphisms (SNPs) in eight ESTs. We investigated the associations of these SNPs with 18 carcass and meat quality traits in a Landrace x Lantang F-2 resource population (n = 257). Association analysis revealed that seven SNPs (except E42) were associated with some of the carcass- and meat quality-related traits. Particularly, significant associations of three SNPs (E53, E82, and E36) with backfat thickness traits were observed. Further, the genetic effects of E53 on four live backfat thickness traits were validated in an independent population (n = 221). More investigations about E53 sequence characteristics were performed, i.e., radiation hybrid (RH) mapping, 3'-RACE, and screening analysis of the positive BAC clones. Our research identified the genetic effects of eight EST-derived SNPs on carcass and meat quality traits, and suggested that E53 may be a useful marker for live backfat thickness traits in pig breeding programs.