VecScreen is a system for quickly identifying segments of a nucleic acid sequence that may be of vector origin. NCBI developed VecScreen to combat the problem of vector contamination in public sequence databases. This Web page is designed to help researchers identify and remove any segments of vector origin before sequence analysis or submission.

Failure to recognize foreign segments in a sequence can:

• lead to erroneous conclusions about the biological significance of the sequence
• waste time and effort in analysis of contaminated sequence
• delay the release of the sequence in a public database
• pollute public databases with contaminated sequence