Correlation Between Variations In Promoter Region Of BMPER And FABP2 Genes And Intramuscular Fat Content In Pigs

Intramuscular fat (IMF) content is the most critical factor which affects pork quality. Generally, the lower of IMF, the lower of muscle juicy、tenderness、flavor and overall acceptability. Increasing IMF content is an effective way to improve the sensory quality and edible quality of pork, therefore, IMF has become a research hotspot in animal husbandry, especially in genetic and breeding field.This research chose BMPER and FABP2 genes as candidate genes on the basis of previous SNP chip analysis. Not only studied the relativity between promoter variations and IMF content but also verified and analysised the function of those SNPs.The first experiment verified the effect of SNPs in the promoter of BMPER on IMF deposition. Firstly, c.-1344 A>C and c.-1423 A>G were found by DNA pool constructing、 BMPER promoter amplifying and directly sequencing. Then the two loci were genotyped by PCR-SSCP technology and only AA/AA and GC/GC two genotypes were found in Duroc × Large White x Yorkshire (D×L×Y) marketing pigs. Further study found that AA/AA genotype showed a higher IMF content and expression level than GC/GC genotype (p<0.05), fluorescence activity analysis also revealed AA haplotype promoter activity was significantly higher than GC haplotype (p<0.01).The second experiment validated SNPs in the promoter region of FABP2 gene have an function on IMF content and expression level of FABP2. Firstly, c.-1488C/T、c.-1485G/A、 c.-1471T/C、c.-1407T/C、c.-1404A/G were found by direct sequencing the promoter of FABP2, then the 5 SNPs were genotyped in a larger sample and analysised by Haploview software, results showed that the 5 SNPs were linked completely, fluorescence activity analysis showed that the transcription level of CGTTA haplotype was significantly higher than TACCG haplotype (p<0.01), but the IMF content of CGTTA/CGTTA genotype was significantly lower than TACCG/TACCG genotype (p<0.01).