What is CRISPR, and why does it matter for cell biology?
CRISPR-Cas9 is a gene editing system adapted from a natural bacterial immune defence. Bacteria store short fragments of DNA from viruses that once infected them in regions of their genome called CRISPR arrays (Clustered Regularly Interspaced Short Palindromic Repeats). When the same virus attacks again, the bacterium copies these fragments into guide RNAs that direct the Cas9 enzyme to cut the invader's DNA at a matching sequence, destroying it.
Researchers repurposed this system as a programmable editing tool. By designing a synthetic guide RNA that matches almost any DNA sequence, Cas9 can be directed to cut a specific gene inside a living cell rather than a virus. That ability to target a precise DNA sequence on demand is what makes CRISPR the most widely adopted genome editing platform in life science research today, replacing older, less efficient tools such as zinc finger nucleases and TALENs.
sgRNA (single guide RNA)
A short synthetic RNA sequence that matches the target gene and physically directs Cas9 to the correct location in the genome.
PAM site
A short DNA sequence adjacent to the target that Cas9 requires in order to bind and cut; it acts as a molecular checkpoint.
Double-strand break (DSB)
The cut Cas9 makes across both strands of the DNA helix at the target site.
NHEJ repair
Non-homologous end joining, the cell's default, error-prone repair pathway; the small insertions or deletions it introduces are what knock out the gene.
Everything you need to knock out a gene, without running the edit yourself
2,000+ ready-to-use KO lines
A continuously growing inventory of pre-made knockout cell lines available for immediate delivery, searchable by gene name, symbol, or accession number.
Flat-fee knockout generation
Can't find your gene or cell line listed? abm generates a custom KO, regardless of cell line, covering design through validation.
QC data included with every line
Each knockout cell line arrives with supporting quality control data confirming the edit, so you can move straight into experiments.
Faster than a DIY project
Skip sgRNA design, cloning, delivery optimization, and clonal screening, and start with a confirmed knockout instead.
Cell line insurance available
Protect your investment against growth issues, thawing failures, or freezer breakdowns with abm's optional Cell Line Insurance.
Generating a knockout in-house vs. ordering one from abm
DIY: In-house CRISPR editing
- Design and validate sgRNAs from scratch
- Source and troubleshoot Cas9 delivery reagents
- Optimize transfection or transduction conditions
- Isolate and screen single-cell clones by hand
- Confirm the edit before starting your real experiment
abm: Ready-made or custom KO line
- Select an in-stock KO line or request any gene/cell line combination
- sgRNA design, delivery, and clonal screening handled for you
- Delivered with supporting QC data confirming the knockout
- Go straight into your assay, not another optimization project
Search the ready-to-use CRISPR KO collection
Enter a gene name, symbol, or accession number to search more than 2,000 knockout cell lines available for immediate delivery.
Examples: TP53, BRCA1, EGFR, HEK293T, or an NCBI accession number.
Common questions about CRISPR knockout cell lines
Learn how CRISPR knockout cell lines are generated, what is included with each line, and when a custom KO or Cas9-expressing background is the better fit.
What is a CRISPR knockout (KO) cell line?
How does CRISPR-Cas9 gene editing work?
What's the difference between a CRISPR KO cell line and a Cas9-expressing cell line?
Which cell backgrounds are available as ready-to-use KO cell lines?
Can I get a gene or cell line knocked out that isn't already listed?
What quality control data comes with each knockout cell line?
Why order a knockout instead of running the CRISPR edit myself?
Need to knock out more than one gene in the same background?
Start from an abm Cas9-expressing stable cell line and introduce your own sgRNA library or custom guide, ideal for multi-gene screens and knock-in projects that need a repair template.