Introduction
CHOPCHOP is a web-based tool for identifying optimal CRISPR-Cas single guide RNA (sgRNA) target sites. Given a target gene, genomic sequence, or chromosome coordinates, CHOPCHOP scores and ranks potential target sites using up-to-date algorithms. The tool supports multiple CRISPR systems and is managed by ELIXIR Norway.
Key Features
- Multi-system support — works with Cas9, Cpf1, and TALEN targeting systems
- Flexible input — accepts gene names, genomic sequences, or chromosome coordinates across many organisms
- Ranked results — scores and ranks candidate target sites based on predicted efficiency and specificity
- Configurable parameters — default mode for quick results, advanced mode for fine-tuned control over scoring and filtering
- Web-based — no software installation required; runs entirely in the browser
Getting Started
Navigate to the CHOPCHOP web interface, select your organism and CRISPR mode, and enter your target gene or coordinates. Results are displayed with ranked sgRNA candidates ready for experimental design.