秦川肉牛FABP3及FABP4基因SNP与肉质性状的关联性

SNP detection of FABP3 and FABP4 genes of Qinchuan and their association with meat traits beef cattle

【目的】探索脂肪酸结合蛋白3(Fat acid binding proteins 3,FABP3)及脂肪酸结合蛋白4(FABP4)基因对秦川牛肉用新品系肉用性状的影响,为秦川肉牛的选育提供理论基础。【方法】随机选择18~24月龄健康的秦川肉牛571头,尾静脉采血10mL/头,提取血液DNA,PCR扩增FABP3及FABP4基因,检测其单核苷酸多态性(SNP)位点,并分析SNP位点基因型和单倍型组合对肉牛肉用性状(背膘厚、眼肌面积、肌间脂肪含量)的影响。【结果】测序发现,在FABP3基因第3个内含子上检测出1个SNP位点:g.60298C>T。在FABP4基因第1个内含子上检测出2个SNP位点:g.2686A>T和g.2834C>G;在第4外显子上检测出1个SNP位点:g.4220A>G。FABP3基因g.60298C>T位点不同基因型的肌内脂肪含量差异显著(P<0.05),TT基因型显著高于CT和CC基因型。对FABP4基因而言,g.2834C>G位点上的CC基因型肉用性状表现较优,其眼肌面积极显著高于GG和CT基因型(P<0.01),肌内脂肪含量显著高于GG和CG基因型(P<0.05);g.4220A>G位点上的TT基因型的肉用性状较优,其背膘厚显著高于CC和CT基因型(P<0.05)。H1H1是最优秀的单倍型组合,其眼肌面积和肌内脂肪含量分别极显著高于单倍型组合H3H3和H3H7(P<0.01)。【结论】FABP3及FABP4基因与秦川牛肉用新品系肉用性状关联紧密。

【Objective】In this study,the effects of FABP3 and FABP4 genetic variations on meat traits of Qinchuan beef cattle were evaluated to provide basis for breeding of Qinchuan beef cattle.【Method】A total of 571 Qinchuan beef cattle at the age of 18-24 months were chosen and blood samples with 10 ml were collected at the tail vein.Then,we extracted DNA of blood and the genes were cloned by PCR.The SNPs of FABP3 and FABP4 genes were amplified and effects of haplotypes and combined genotypes on meat traits（backfat thickness,ultrasound lean muscle area and intramuscular fat）were analyzed.【Result】There was one SNP（g.60298 C〉T）in FABP3 third intron,while there were three SNPs sites in FABP4 totally,located at g.2686 A〉T and g.2834 C〉G of first intron and g.4220 A〉G of fourth exon.Single nucleotide polymorphism（g.60298 C〉T）of FABP3 was positively correlated with intramuscular fat（P〈0.05）,and the individuals with TT homozygotes had significantly higher IMF than those with CT genotype and CC genotype（P〈0.01）.At g.2834 C〉G locus of FABP4,the individuals with CC homozygotes had higher ultrasound lean muscle area than GG and CG genotype significantly（P〈0.05）.At g.4220 A〉G locus,the individuals with TT homozygotes had higher backfat thickness than CC and CT genotype significantly（P〈0.05）.H1H1（ACA-ACA）diplo type had better performance than H3H3（AGA-AGA）in ULA（P〈0.01）and H3H7（AGA-TGA）in IMF（P〈0.01）.H1H1 was the most superior combined genotype.【Conclusion】SNPs mutations in FABP3 gene and FABP4 had significant impacts on meat traits of Qinchuan beef cattle.