Genetic diversity and phylogenetic analysis of Aleutian mink disease virus isolates in north-east China

Abstract

Aleutian mink disease is the most important disease in the mink-farming industry worldwide. So far, few large-scale molecular epidemiological studies of AMDV, based on the NS1 and VP2 genes, have been conducted in China. Here, eight new Chinese isolates of AMDV from three provinces in north-east China were analyzed to clarify the molecular epidemiology of AMDV. The seroprevalence of AMDV in north-east China was 41.8% according to counterimmuno-electrophoresis. Genetic variation analysis of the eight isolates showed significant non-synonymous substitutions in the NS1 and VP2 genes, especially in the NS1 gene. All eight isolates included the caspase-recognition sequence NS1:285 (DQTD↓S), but not the caspase recognition sequence NS1:227 (INTD↓S). The LN1 and LN2 strains had a new 10-amino-acid deletion in-between amino acids 28-37, while the JL3 strain had a one-amino-acid deletion at position 28 in the VP2 protein, compared with the AMDV-G strain. Phylogenetic analysis based on most of NS1 (1755 bp) and complete VP2 showed that the AMDV genotypes did not cluster according to their pathogenicity or geographic origin. Local and imported ADMV species are all prevalent in mink-farming populations in the north-east of China. This is the first study to report the molecular epidemiology of AMDV in north-east China based on most of NS1 and the complete VP2, and further provides information about polyG deletions and new variations in the amino acid sequences of NS1 and VP2 proteins. This report is a good foundation for further study of AMDV in China.

Molecular epidemiology of Aleutian mink disease virus from fecal swab of mink in northeast China

“…Morever, 23 Chinese samples had similar changes in some fixed positions, especially in the hypervariable regions. These results indicated that Chinese AMDV strains had a high degree of similarity among themselves, while they showed the difference from ADMV strains in other countries, which is consistent with the previous studies [ 9 , 13 ].…”

“…Currently, there is no available vaccine, and the knowledge about AMDV diversity and molecular epidemiology will help to prevent AMD from spreading. Previous studies reported that a large number of mink farms were affected by AMDV in China, based on VP2 or NS1 gene from samples of mink tissues, such as spleen, and plasma, especially during the pelting season [9,10]. However, this epidemiological survey of AMDV is commonly limited by sampling time and quantity.…”

“…Previous studies reported that a large number of mink farms were affected by AMDV in China, based on VP2 or NS1 gene from samples of mink tissues, such as spleen, and plasma, especially during the pelting season [ 9 , 10 ]. However, this epidemiological survey of AMDV is commonly limited by sampling time and quantity.…”

“…At present, only a few molecular epidemiological reports of AMDV isolated from tissue or blood have been studied [ 9 – 11 ]. Since AMD infection can be transmitted in the mink farming industry through feces, fecal samples are feasible for detecting AMDV.…”

Molecular epidemiology of Aleutian mink disease virus from fecal swab of mink in northeast China

“…Morever, 23 Chinese samples had similar changes in some fixed positions, especially in the hypervariable regions. These results indicated that Chinese AMDV strains had a high degree of similarity among themselves, while they showed the difference from ADMV strains in other countries, which is consistent with the previous studies [9,15].…”