Post-Screen Analysis

When reviewing screening data, a library .chip file will be a useful resource. How to Pick a .chip File from the GPP from the GPP provides a walkthrough of what a .chip file is and how to pick the correct one.

GPP has developed a web tool, Apron Beta , to assist with the analysis of pooled screens. Apron currently supports analysis of CRISPRko, CRISPRa, and CRISPRi screens conducted with either Cas9 or Cas12a, so long as each construct targets a single gene, regardless of the number of guides in each construct targeting that gene. The accompanying Pooled Screen Analysis with Apron user guide provides step-by-step instructions as well as suggestions for how to approach screen analysis.

Base editing screen analysis guidance is described separately in our Base Editing Data Analysis Guide.

FAQs:

Q: How does GPP deconvolute sequencing data?

GPP uses an internal software tool, PoolQ, to deconvolute and quantitate perturbation barcodes in multiplexed sequencing data. For more detail on how PoolQ works, review the information on the PoolQ Software Tool Downloads page.

Q: Is there additional information available on screen analysis?

For further reading on conducting screen analysis, please see Design and analysis of CRISPR-Cas experiments.

Project PlanningAssay DevelopmentScreeningPost-Screen AnalysisScreen Follow-UpSummary Tables

GPP Web Portal Terms of Service

Effective Date: December 8, 2025
By using this site, you agree to our terms and conditions below.

Overview of Terms

The data made available on this website were generated for research purposes and are not intended for clinical or commercial uses. Commercial use (or other use for profit-making purposes) of the GPP Web Portal and its tools, is not permitted under these terms and may require a separate license agreement from Broad or its contributors. For more information, please contact partnering@broadinstitute.org.

The original data may be subject to rights claimed by third parties, including but not limited to, patent, copyright, other intellectual property rights, biodiversity-related access and benefit-sharing rights. It is the responsibility of users of Broad Institute services to ensure that their use of the data does not infringe any of the rights of such third parties.

Any questions or comments concerning these Terms of Use can be addressed to: legal@broadinstitute.org.

By accessing and viewing this GPP Web Portal, you agree to the following terms and conditions:

Attribution

You agree to acknowledge the Broad Institute (e.g., in publications, services or products) for any of your use of its online services, databases or software in accordance with good scientific practice. You agree to use the acknowledgment wording provided for the relevant tools as indicated on the FAQ for each tool.

Updating the Terms of Use

We reserve the right to update these Terms of Use at any time. When alterations are inevitable, we will attempt to give reasonable notice of any changes by placing a notice on our website, but you may wish to check each time you use the website. The date of the most recent revision will appear on this, the "GPP Web Portal Terms of Use" page. If you do not agree to these changes, please do not continue to use our online services. We will also make available an archived copy of the previous Terms of Use for comparison.

Indemnification and Disclaimer of Warranties

You are using this GPP Web Portal at your own risk, and you hereby agree to hold Broad and its contributors and their trustees, directors, officers, employees, and affiliated investigators harmless for any third party claims which may arise from your use of the GPP Web Portal, the tools available therein, or any portion thereof. Further, you agree to indemnify Broad, its contributors, and its and their trustees, directors, officers, employees, affiliated investigators, students, and affiliates for any loss, costs, claims, damages, or other liabilities arising from any unpermitted commercial or profit-making use you make of the GPP Web Portal. The GPP Web Portal is a research tool and is provided "as is". Broad does not represent that the GPP Web Portal is free of errors or bugs or suitable for any particular tasks.

ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT, OR THE ABSENCE OF LATENT OR OTHER DEFECTS ARE DISCLAIMED. IN NO EVENT SHALL BROAD OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THE GPP WEB PORTAL, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Governing Law

The terms and conditions herein shall be construed, governed, interpreted, and applied in accordance with the internal laws of the Commonwealth of Massachusetts, U.S.A. Furthermore, by accessing, downloading, or using the Database, You consent to the personal jurisdiction of, and venue in, the state and federal courts within Massachusetts with respect to Your download or use of the Database.