5个绿壳蛋鸡群体中EAV-HP在SLCO1B3基因5'-非编码区插入整合频率和类型的研究

本试验旨在测定和比较5个绿壳蛋鸡群体中EAV-HP在溶质载体有机阴离子转运蛋白家族成员1B3(solute carrier organic anion transporter family member 1B3,SLCO1B3)基因的5'-非编码区插入整合的频率和类型。所选5个绿壳蛋鸡群体包括3个北京地区的商业群体(北京-LK、北京-LF和北京-YM)、贵州长顺绿壳蛋鸡群体和四川省地方品种旧院黑鸡;采用双重PCR对EAV-HP的插入整合进行检测,并利用DNA测序的方法判断EAV-HP的主要突变位点。结果表明,5个绿壳蛋鸡群体均拥有一定数量的EAV-HP插入整合的个体,表现为杂合(LC/N)和纯合(LC/LC)基因型,均可产绿壳蛋,其中旧院黑鸡的绿壳蛋频率最低,仅为28.90%,其次是北京-LF群体,为46.94%,其他3个群体的绿壳蛋频率为83.33%~84.62%;经卡方检验,北京-LF和旧院黑鸡群体符合Hardy-Weinberg平衡(P>0.05),而其他3个群体则极显著偏离Hardy-Weinberg平衡状态(P<0.01)。DNA测序结果显示这5个绿壳蛋鸡群体中EAV-HP插入整合的序列与之前报道的东乡绿壳蛋鸡的KC632577.1完全一致。地方品种旧院黑鸡的绿壳蛋频率较低,建议利用双重PCR检测的分子标记辅助选择方法加以提高。

Frequency and Type of EAV-HP Insertion in the 5'-flanking Region of SLCO1B3 Gene in Five Blue-egged Chicken Populations

The objective of the study was to examine the frequency and type of EAV-HP insertion in the 5'-flanking region of SLCO1B3 gene in five blue-egged chicken populations. The selected populations included three commercial populations sampled in Beijing (Beijing-LK,Beijing-LF and Beijing-YM),Changshun Blue-egged chicken in Guizhou province and indigenous Jiuyuan Black chicken in Sichuan province. A duplex PCR method was employed to detect the EAV-HP insertion and a region carrying four nucleotide variation within the EAV-HP was further sequenced to verify its type. The results showed that all the five populations had a certain proportion of individuals carrying the EAV-HP insertion. Among which,Jiuyuan Black chicken had the lowest frequency of blue-egged (LC/N,LC/LC) genotype (28.90%) followed by the Beijing-LF population (46.94%),while the remaining three populations all reached very high frequencies (83.33% to 84.62%). Jiuyuan Black chicken and Beijing-LF population were under the Hardy-Weinberg equilibrium (P>0.05),but other three populations significantly deviated from the Hardy-Weinberg equilibrium (P<0.01). DNA sequence of a region of the EAV-HP carrying four nucleotide variation showed that the EAV-HP insertion identified among these five populations shared the same reference sequence that was previously reported in Dongxiang chicken (KC632577.1). In conclusion,the frequency of blue eggshell in indigenous Jiuyuan Black chicken was generally low and it could be easily enhanced by a marker-assisted selection through the established duplex PCR method.