Ex-FABP基因5'UTR遗传变异及其与鸡脂肪性状关系的研究

Genetic Variation of 5'UTR of Ex-FABP Gene and the Relationship with Fat Traits in Chickens

以Ex-FABP为候选基因,采用直接测序方法寻找贵妃鸡、怀乡鸡母鸡Ex-FABP基因的SNP,在基因5′调控区筛查到3个多态位点G2707A、C2717A、T2725G,用生物信息学和PCR-RFLP方法分析并验证这3个位点。结果显示:只有位点G2707A存在一个SacⅡ酶切位点;三位点多态信息含量:其中贵妃鸡母鸡的PIC均为0,表现为单态;怀乡鸡母鸡的PIC分别为0.3723、0.3749、0.3727,处于中度多态。经过χ2适合性检验,所有母鸡群体在该位点处于Hardy-Weinberg非平衡状态(P<0.05)。比较G2707A位点的3种基因型GG、GA和AA对怀乡鸡母鸡群体脂肪性状的影响,结果基因型对皮脂厚、肌内脂肪没有显著影响;但在活重、屠体重性状方面,GA型显著高于GG型(P<0.05);腹脂重和腹脂率,GG>GA型(P<0.05),并有GG>AA>GA型的趋势。生物信息学分析显示,该突变位点没有处于转录因子结合位点,不会影响基因转录。

Three new SNPs,G2707A,C2717A,T2725G,in 5＇UTR of Ex-FABP gene were detected through the direct sequencing method in Huaixiang and Princess hen,which were analyzed by Bioinformatics and PCR-RFLP. The results showed that only the locus of G2707A had the enzyme cut loei;PIC of Princess hen was zero and monomorphism; Huaixiang hen showed moderate polymorphism and PIC were 0.3723,0.3749,0.3727. The X2 test indicated that the polymorphsim locus in all chickens were not fit Hardy-Weinberg equilibrium （P〈0.05）. The effects of genotypes （AA,GA, GG） of G2707A loci on Huaixiang hen＇s body fat traits showed that genotypes had no significant effects on intramuscular fat and subcutaneous fat thick （P〉0.05）. For body weight and carcass weight,the genotype GA was significantly higher than that of GG （P〈0.05）. On abdominal fat weight and rate,the genotype GG had higher value than GA,and their value appeared to have GG 〉AA 〉GA tendency. Bioinfoimatics analysis demonstrated that the variation was not in the transcription factor binding site and couldn＇t affect Ex-FABP transcription.