[Gene characterization of the VP1 region of Coxsackievirus A4 from herpangina cases in Shenzhen of China].

OBJECTIVE

To analyze the phylogeny of the VP1 region of Coxsackie virus A4 (CVA4) from herpangina cases of Shenzhen in 2012 and 2014.

METHODS

Real-time reverse transcription(RT)-PCR method was used to test virus such as human enterovirus71, coxsackievirus A16, coxsackievirus A4, coxsackievirus A6 and coxsackievirus A10. The VP1 gene of CVA4 positive samples were amplified by RT-PCR and sequenced. Then the homology and phylogeny analysis of the CVA4 VP1 region was performed.

RESULTS

The six CVA4 isolates identified in the herpangina cases during 2012 and 2014 were mostly closed with GIb genotypes. The nucleotide and amino acid homology between them were 94.1% (nucleotide mutation rate was 5.9%) and 98.3%, five amino acid mutation were found in CVA4 strain 2014 of Shenzhen: aa22N-S, aa34T-A, aa63N-S, aa165A-D, aa200T-A. The phylogenetic analysis based on VP1 region demonstrates that CVA4 strain of Shenzhen in 2012 had the nearest genetic relationship with CVA4 strain of Shandong isolated in 2010 (KF150144). However, CVA4 strain of Shenzhen in 2014 had the nearest genetic relationship with CVA4 strain of Jilin (JQ715709) isolated in 2006.

CONCLUSIONS

It reveals that all CVA4 strains from the two outbreak of herpangina belong to genotype GIb, the degree of variation in VP1 region of CVA4 strain of Shenzhen in 2014 is obvious compared with that in 2012.There is an obvious difference on internal trend of evolution lineage between the CVA4 strains from 2012 and 2014.