The advent of molecular methods, such as DNA sequencing, has facilitated a rapid development of hypotheses for phylogenetic relationships among biological groups. The amount of DNA sequences that can be used in phylogenetic inference is growing at an increasingly fast pace. There are, as of now, more than 135 million sequences in GenBank 
and 1.5 million DNA barcodes in BOLD 
. Thanks to the development of new techniques and the possibility to outsource the processes involved, DNA sequencing is becoming cheaper and quicker. Thus, research groups might need the use of an efficient system in order to keep track of, manage and annotate their DNA sequences. In addition to adequate storage of DNA sequences, it would be advantageous if this system facilitates further processing of the data such as easy creation of datasets for phylogenetic analysis, quick creation of tables ready for publication and submission of sequences to public repositories (e.g. GenBank).
Relational databases permit organized storage of information that can be searched and retrieved quickly, depending on (and flexible to) the needs of users. However, relational databases such as MySQL need to be coupled with a software interface designed to act as a bridge between users and relational database for uploading, managing and retrieving e.g. DNA sequence and voucher specimen data.
Although there are several database systems available that handle biological and molecular data, they are conceived to be multipurpose systems 
. Current biological databases handle a variety of information such as scientific names, current taxonomic classification, voucher images, geographic distribution maps, bibliographic references and so on. The Scratchpads project 
is a social network portal for managing, sharing and publishing taxonomic information and voucher data online, but includes very limited capabilities for handling DNA sequence data (e.g. The Holometabola Insects Phylogenetic Database is based on Scratchpads 
). The Lifedesks platform 
hold taxonomic information and specimen data connected to voucher specimens in EOL, but there are no capabilities for storing and processing DNA sequences. The Mantis biological database manager allows storage of taxonomic and specimen data for museum collections 
. These systems allow being configured so that they can used as private working platforms restricted to members of a research group.
The Barcode of Life Database (BOLD 
) is both a public repository of DNA barcodes (and voucher data) and an online workbench module to collect and analyze DNA barcode sequences (a segment of the COI gene), but offers limited functionality for other gene markers as well as for dataset creation. Another commonly used database to store DNA sequences is GenBank, which is an excellent repository of data. However, GenBank is mainly used as a repository of sequences after they have been managed and analyzed during the research process. After the analysis of sequences is finished, the sequences are submitted to GenBank during the preparation of manuscripts. In this way, GenBank becomes a repository of end-products (sequences) of the research process.
Thus, there is a need for a database system that can be used to store and manage DNA sequences during the research process. This system should facilitate the aggregation of sequences into dataset files ready-to-run in common phylogenetic software. It should be able to handle the amount of data normally used during phylogenetic research: such as biological data from hundreds of voucher specimens and thousands of DNA sequences for a number of gene markers.
Here we present VoSeq, a user friendly database system designed for day to day use by researchers in phylogenetic inference to store and organize DNA sequences. VoSeq also stores complementary data such as voucher photos, collection data, taxonomic classification and collection locality maps. VoSeq can be downloaded and installed by on-screen instructions on a private computer, or installed on a shared server so that it can be used as a web application restricted to a research group or a network of collaborators. The main functionality lies in retrieving ready-to-run datasets for phylogenetic analyses for various software, complete with partition tables and analysis specifications, as well as MS Excel tables for work overview or publications. The platform of this database is taxon independent and can be used for all organisms. The source code is freely available under the GNU General Public License v2. Additionally, VoSeq has been designed to be cooperative with other biological web-based databases. For this, we included features of the so-called Web 2.0 
such as the Ajax protocol for user-friendliness, and exchange of information over the Internet based on SOAP and REST calls using the XML and JSON formats.