The CRISPR-Cas9 system can edit any DNA sequence in any organism without the need for a specific guide RNA sequence.

The statement is false because CRISPR‑Cas9 relies on a guide RNA to direct the Cas9 enzyme to a specific DNA sequence; without that guide, Cas9 cannot recognize or cut the target. The guide RNA is designed to match the DNA sequence you want to edit, forming a complementary pair that positions Cas9 exactly where the cut should occur. Once the guide RNA binds the target, Cas9 creates a double‑strand break, and the cell repairs it, allowing the insertion or deletion of nucleotides. For example, to delete a faulty gene in a human cell, scientists design a guide RNA that matches the gene’s sequence, then deliver the guide RNA and Cas9 protein into the cell, where Cas9 cuts the DNA and the cell repairs it, removing the harmful part. Thus, a specific guide RNA is essential for accurate, targeted genome editing.