Muscle lipid metabolism gene expression in pigs with different H-FABP genotypes

Previous studies indicated that polymorphism in heart fatty acid binding protein gene (H-FABP) was significantly associated with pig intramuscular fat (IMF) content. However, the mechanism of it was not completely clear yet. This study was to investigate the expression level of lipid metabolism genes among H-FABP genotypes using Real-time PCR. Zhaotong Wujin pigs had polymorphism at Hinf I-RFLP and Hae III-RFLP location, and displayed genotypes of HH, Hh, hh and DD, Dd, dd, respectively. The effect of H-FABP genotypes at Hinf I and Hae III site on IMF content were HH > Hh > hh, dd > Dd > DD. Monounsaturated fatty acids (MUFA) exhibited the similar H-FABP genotypes as IMF content. Significantly higher H-FABP mRNA and protein expression levels were found for the Hinf I PCR-RFLP HH and Hae III PCR-RFLP dd genotypes comparing with other genotypes. Expression of genes, including FAS, SCD, SREBP-1c and LPL was significantly higher in Hinf I PCR-RFLP HH and Hae III PCR-RFLP dd genotypes (P < 0.05) than in other genotypes. This result suggested that H-FABP genotypes affect the IMF content and fatty acid composition in Zhaotong Wujin pigs. Higher IMF content in pigs with Hinf I PCR-RFLP HH and Hae III PCR-RFLP dd genotypes may result from the higher H-FABP mRNA and protein expression, and the higher expression level of lipogenic genes.