Porcine Is a Positional Candidate Gene Associated with Growth and Fat Deposition

Abstract

Crosses between Korean and Landrace pigs have revealed a large quantitative trait loci (QTL) region for fat deposition in a region (89 cM) of porcine chromosome 4 (SSC4). To more finely map this QTL region and identify candidate genes for this trait, comparative mapping of pig and human chromosomes was performed in the present study. A region in the human genome that corresponds to the porcine QTL region was identified in HSA1q21. Furthermore, the LMNA gene, which is tightly associated with fat augmentation in humans, was localized to this region. Radiation hybrid (RH) mapping using a Sus scrofa RH panel localized LMNA to a region of 90.3 cM in the porcine genome, distinct from microsatellite marker S0214 (87.3 cM). Two-point analysis showed that LMNA was linked to S0214, SW1996, and S0073 on SSC4 with logarithm (base 10) of odds scores of 20.98, 17.78, and 16.73, respectively. To clone the porcine LMNA gene and to delineate the genomic structure and sequences, including the 3′untranslated region (UTR), rapid amplification of cDNA ends was performed. The coding sequence of porcine LMNA consisted of 1,719 bp, flanked by a 5’UTR and a 3’UTR. Two synonymous single nucleotide polymorphisms (SNPs) were identified in exons 3 and 7. Association tests showed that the SNP located in exon 3 (A193A) was significantly associated with weight at 30 wks (p<0.01) and crude fat content (p<0.05). This association suggests that SNPs located in LMNA could be used for marker-assisted selection in pigs.

Keywords

• SSC4
• Linkage Mapping
• QTL Mapping
• Pig