SEQUENCE COMPARISON OF THE NONSTRUCTURAL GENES OF 4 DIFFERENT TYPES OF ALEUTIAN-MINK-DISEASE PARVOVIRUS INDICATES AN UNUSUAL DEGREE OF VARIABILITY

The present work shows that at least four different sequence types of Aleutian mink disease parvovirus (ADV) are present in ADV isolates fro m mink. We here report the nucleotide sequences of these four types of ADV from nucleotide 123 to 2208 (map unit 3 to 46). This part of the genome encodes three non-structural (NS) proteins of ADV. Comparison o f the deduced amino acid sequences of these NS proteins showed that th e ADV proteins are much less conserved than the NS proteins from other members of the autonomous group of parvoviruses. In general, we found that the middle region of the ADV NS-1 protein was relatively well co nserved among the types, while both the amino and carboxy-terminal end s of the protein had higher amino acid variability. Interestingly, the putative NS-3 protein from type 3 ADV is truncated in the carboxy-ter minal end. The molecular evolutionary relationship among the four type s of ADV was examined. This analysis, taken together with the unusuall y high degree of variability of the ADV types, indicates that the ADV infection in mink is likely to be an old infection compared to the oth er parvovirus infections or, alternatively, that ADV accumulates seque nce changes much faster than other parvoviruses.