Unknown

Dataset Information

0

Molecular epidemiology of avian leukosis virus subgroup J in layer flocks in China.


ABSTRACT: Avian leukosis virus subgroup J (ALV-J) was first isolated from meat-type chickens in 1988. No field cases of ALV-J infection or tumors in layer chickens were observed worldwide until 2004. However, layer flocks in China have experienced outbreaks of this virus in recent years. The molecular epidemiology of ALV-J strains isolated from layer flocks was investigated. The env genes of 77.8% (21/27) of the ALV-J layer isolates with a high degree of genetic variation were significantly different from the env genes of the prototype strain of ALV-J (HPRS-103) and American and Chinese strains from meat-type chickens (designated ALV-J broiler isolates). A total of 205 nucleotides were deleted from the 3' untranslated region of 89.5% (17/19) of the ALV-J layer isolates. Approximately 94.7% (16/17) of the layer isolates contained a complete E element of 146 to 149 residues. The U3 sequences of 84.2% (16/19) of the ALV-J layer isolates displayed less than 92.5% sequence homology to those of the ALV-J broiler isolates, although the transcriptional regulatory elements that are typical of avian retroviruses were highly conserved. Several unique nucleotide substitutions in the env gene, the U3 region, and the E element of most of the ALV-J layer isolates were detected. These results suggested that the env gene, E element, and U3 region in the ALV-J layer isolates have evolved rapidly and were significantly different from those of the ALV-J broiler isolates. These findings will contribute to a better understanding of the pathogenic mechanism of layer tumor diseases induced by ALV-J.

SUBMITTER: Gao Y 

PROVIDER: S-EPMC3295186 | BioStudies | 2012-01-01

REPOSITORIES: biostudies

Similar Datasets

2011-01-01 | S-EPMC3310751 | BioStudies
2016-01-01 | S-EPMC5120538 | BioStudies
2019-01-01 | S-EPMC6854487 | BioStudies
2014-01-01 | S-EPMC3979936 | BioStudies
2012-01-01 | S-EPMC3457325 | BioStudies
2014-01-01 | S-EPMC3986388 | BioStudies
1998-01-01 | S-EPMC110618 | BioStudies
2004-01-01 | S-EPMC516401 | BioStudies
2010-01-01 | S-EPMC2931761 | BioStudies
1000-01-01 | S-EPMC5877346 | BioStudies