Virus variation resources at the National Center for Biotechnology Information: dengue virus

We have created an integrated web resource for dengue virus. The technology developed for the NCBI Influenza Virus Resource has been extended to process non-segmented dengue virus genomes. In order to allow efficient processing of the dengue genome, which is large in comparison with individual influenza segments, we developed an offline pre-alignment procedure which generates a multiple sequence alignment of all dengue sequences. The pre-calculated alignment is then used to rapidly create alignments of sequence subsets in response to user queries. This improvement in technology will also facilitate the incorporation of additional virus species in the future. The set of virus-specific databases at NCBI, which will be referred to as Virus Variation Resources (VVR), allow users to build complex queries against virus-specific databases and then apply exploratory data analysis tools to the results. The metadata is automatically collected where possible, and extended with data extracted from the literature.The NCBI Dengue Virus Resource integrates dengue sequence information with relevant metadata (sample collection time and location, disease severity, serotype, sequenced genome region) and facilitates retrieval and preliminary analysis of dengue sequences using integrated web analysis and visualization tools.The National Center for Biotechnology Information (NCBI) Virus Variation Resources (VVR) provide web retrieval interfaces, analysis and visualization tools for virus sequence datasets. In this paper we describe the recent extension of the collection of resources to include the Dengue Virus Resource in addition to the existing Influenza Virus Resource [1,2]. The NCBI Dengue Virus Resource was created to support a collaborative effort by the National Institute of Allergy and Infectious Diseases (NIAID), the Broad Institute, and the Novartis Institute for Tropical Diseases (NITD) to create a large collection of complete dengue genome sequences and provide access to the