Xu Gang, Liu Xiao-Yu, Zhao Ye, Chen Yang, Zhao Jing, Zhang Guo-Zhong
Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian, Beijing, 100193, People's Republic of China.
Virol J. 2016 Mar 9;13:40. doi: 10.1186/s12985-016-0497-3.
Infectious bronchitis is a severe disease caused by infectious bronchitis virus (IBV) that affects fowl flocks worldwide. The understanding of the mechanisms involved in IBV evolution and variation would provide important theoretical basis for prevention and control of the disease in the future.
IBV strain GD was isolated from southern China in 2013 and the complete genome sequencing and phylogenetic analysis were performed.
The genome of approximately 27,680 nt comprised six genes, with insertions and mutations in most of the structural genes. The S1 gene showed the highest identity to strain TW2575/98 isolated in Taiwan, and was distantly related to the H120 vaccine strain. Phylogenetic analysis showed that the S1 gene of strain GD was also related to that of TW-type strains. Recombination analysis indicated that strain GD was a chimera whose putative parental strains belonged to the QX- and TW-type subgroups.
An increasing number of TW-type strains have been isolated from China in recent years, which is in agreement with our findings, suggesting the emergence and increased prevalence of new TW-type strains in southern China.
传染性支气管炎是由传染性支气管炎病毒（IBV）引起的一种严重疾病，影响着全球的家禽群。了解IBV进化和变异所涉及的机制将为未来该病的预防和控制提供重要的理论基础。
2013年从中国南方分离出IBV毒株GD，并进行了全基因组测序和系统发育分析。
约27,680 nt的基因组由六个基因组成，大多数结构基因存在插入和突变。S1基因与台湾分离的TW2575/98毒株具有最高的同源性，与H120疫苗株亲缘关系较远。系统发育分析表明，GD毒株的S1基因也与TW型毒株的S1基因相关。重组分析表明，GD毒株是一种嵌合体，其假定的亲本毒株属于QX型和TW型亚群。
近年来，中国分离出越来越多的TW型毒株，这与我们的研究结果一致，表明中国南方出现了新的TW型毒株且其流行率增加。
