绵羊脂肪型脂肪酸结合蛋白基因(A-FABP)的变异研究

Variations on ovine adipocyte fatty-acid binding protein(A-FABP)gene

【目的】明确绵羊A-FABP(adipocyte fatty-acid binding protein,A-FABP)基因的变异和单倍型特征.【方法】基于Ensemble数据库中绵羊A-FABP基因全序列,对7个绵羊品种共20个样本的A-FABP基因全序列进行测序分析.【结果】PCR扩增获得绵羊A-FABP基因全长6474bp,A、T、G、C 4种碱基的比例分别为31.48%、33.02%、17.21%和18.29%,A+T平均含量为64.50%,G+C平均含量为35.50%;共发现48处单碱基变异位点和2处微卫星位点M1((TG)n)和M2((TA)n),单一变异位点、2核苷酸变异位点和3核苷酸变异位点比例分别为28.85%、40.4%和0.02%;共发现转换、颠换、插入和缺失4种变异类型,其占变异位点总数的比例分别为45.83%、31.25%、2.08%及20.83%;共发现19种单倍型,单倍型多样度为0.995.【结论】A-FABP基因19个单倍型序列的NJ树分化为2个聚类簇,表明A-FABP基因单倍型最初由2个主要单倍型衍化形成.

【Objective】The paper is aimed at revealing genetic variation and the characteristics of haplotype in sheep.【Method】Based on the complete sequence of ovine A-FABP gene in Ensemble database,the A-FABP gene was sequenced and analyzed in 20 samples collected from 7breeds.【Result】The sequence（6 474bp）of the A-FABP gene was obtained by the PCR process.The average percent of four bases（A,T,G and C）was 31.48%,33.02%,17.21% and 18.29%,respectively,the average content of A＋T and G＋C is 64.50% and 35.50%,respectively.Forty eight variation sites and two microsatellite loci for M1（（TG）n）and M2（（TA）n）were found,the percentage of single variation site,two variation sites and three variation sites was 28.85%,40.4% and 0.02%,respectively.4variation types（transition,transversion,insertion and deletion）were observed,and their ratio was 45.83%,31.25%,2.08%and 20.83%,respective-ly.19 haplotypes were found and the haplotype diversity was 0.995.【Conclusion】The NJ tree constructed by nineteen haplotypes developed two main clusters,which indicated that 19 haplotypes initially derived from two main haplotypes.