Association of a missense mutation in the positional candidate gene glutamate receptor-interacting protein 1 with backfat thickness traits in pigs

OBJECTIVE: Previously, we reported quantitative trait loci (QTLs) affecting backfat thickness (BFT) traits on pig chromosome 5 (SW1482–SW963) in an F2 intercross population between Landrace and Korean native pigs. The aim of this study was to evaluate glutamate receptor-interacting protein 1 (GRIP1) as a positional candidate gene underlying the QTL affecting BFT traits. METHODS: Genotype and phenotype analyses were performed using the 1,105 F(2) progeny. A mixed-effect linear model was used to access association between these single nucleotide polymorphism (SNP) markers and the BFT traits in the F(2) intercross population. RESULTS: Highly significant associations of two informative SNPs (c.2442 T>C, c.3316 C>G [R1106G]) in GRIP1 with BFT traits were detected. In addition, the two SNPs were used to construct haplotypes that were also highly associated with the BFT traits. CONCLUSION: The SNPs and haplotypes of the GRIP1 gene determined in this study can contribute to understand the genetic structure of BFT traits in pigs.