Polymorphism of the porcine miR-30d is associated with adipose tissue accumulation, its fatty acid profile and the ME1 gene expression

The miR-30 gene family includes potential regulators of adipogenesis. We searched for polymorphism in this gene family in 4 pig breeds: Duroc, Pietrain, Polish Landrace (PL), Polish Large White (PLW) and a synthetic line (L990). Altogether 5 single nucleotide polymorphisms (SNPs) in 3 genes were found, including one already known SNP rs340704946 within the pre-miR-30d genomic sequence. An association of the rs340704946 with intramuscular fat (IMF) content, abdominal fat accumulation and daily body mass gain in L990 was found. Moreover, the AG genotype was associated with an increased content of monounsaturated fatty acids (MUFA) in subcutaneous (P=0.027) and visceral fat (P=0.007) tissues when compared to the GG genotype. Analysis of PLW pigs revealed an association of the rs340704946 with transcript level of the ME1 gene in longissimus dorsi (LD) muscle (P=0.002), as well as the ME1 protein product in the LD muscle (P<0.001) and subcutaneous fat (P<0.001). We conclude that the rs340704946 can be considered as a functional polymorphism for pig production traits and fatty acid profile in adipose tissue.