不同鸡品种BTN2基因SNP和INDEL分析

摘要

[目的]研究BTN2基因多态性,为鸡的免疫和抗病育种研究提供候选基因.[方法]选取26个不同鸡品种,对BTN2基因进行目标捕获测序,以NCBI中Gallus gallus的BTN2基因序列号(NC_006103.4)为参照,使用MEGA6软件进行不同鸡种基因序列比对,筛选出BTN2基因外显子和内含子中的SNP、INDEL以及氨基酸的变化,最后制成系统发育进化树.[结果]26个不同鸡种中,BTN2基因的外显子筛选出28个SNP位点,且SNP位点大多发生在Exon8上,氨基酸突变大多为错义突变;内含子筛选出48个SNP位点,多数发生在Intron7上;插入缺失多发生在外显子上.聚类分析图结果表明:26个鸡种分为3大类,文昌鸡、SPF-来航鸡、太湖鸡、萧山鸡等聚为一类,他们都具有耐粗饲、适应性强等特点;溧阳鸡、北京油鸡、如皋鸡等聚为一类,他们都具有肉质鲜美等优点;茶花鸡、仙居鸡、固始鸡、大骨鸡等聚为一类.[结论]不同鸡种中BTN2基因的具有遗传多样性,第8外显子中138 264～138 986位点的SNP可以作为鸡免疫特性的候选标记.%[Objective]The aim of this study was to study the polymorphism of BTN2 gene and to provide candidate gene for chicken disease resistance breeding.[Method]Capturing high throughput sequencing in BTN2 of 26 different chicken breeds using Gallus gallus(National Center for Biotechnology Information)as a reference sequence,we screened SNP,INDEL and amino acid sites and constructed the Phyloge-netic tree.[Result]The results showed that 28 SNP found in the BTN2 expressed region,and the majority of the SNP sites occurred on Exon8.Amino acid mutations were mostly missense mutations,48 intronic SNPs were screened introns,most of which occurred on Intron7.Most of the insertion and deletions occurred on the exons.Phylogenetic tree showed that those chicken breeds could be divided into three categories: ①Wenchang chicken,SPF-Laihang chicken,Taihu chicken and Xiaoshan chicken,all of them had the characteristics of strong feeding and adaptability;②Liyang Chicken,Beijing oil chicken,Rucao chicken,they all had the advantages of delicious meat;③Chahua chicken,Xianju chicken,Gushi chicken,Dagu chicken.[Conclusion]The genetic diversity of BTN2 gene in different Chinese chicken breeds is also demonstrated in this study.The SNP of 138264～138986 in exon 8 can be used as a candidate marker for the immunological characteristics of chickens.