The naive question: if Cas9 already works, why does the field keep inventing new CRISPR enzymes? Because Cas9 is one tool with one set of trade-offs, and not every job suits it. Type V enzymes are a different family chosen for different strengths.
Think of it like cutting tools in a workshop. Cas9 is the well-known utility knife. Type V enzymes — Cas12 and its relatives — are like a smaller, differently-shaped blade: in some cases more compact, in some cases leaving a different kind of cut, in some cases reaching spots the bigger tool can't.
Size matters more than it sounds. Gene-editing therapies often have to be packed into a delivery vehicle with limited room. A smaller enzyme fits more easily. Caribou Biosciences' publication US20250325698A1 covers therapeutic applications of CRISPR Type V systems — these enzymes aimed squarely at treating disease.
The guides change too. Caribou's US20250027078A1 covers DNA-containing guides for Type V systems — a different guide chemistry than the RNA guides Cas9 uses. Different enzyme, different instruction format.
The foundational players are in this space too. The Broad Institute's 2025 grant US12305204B2 on CRISPR enzymes and systems shows the core estate spanning beyond the original tool. The field's anchor institutions aren't standing on Cas9 alone.
The short version: Type V enzymes are CRISPR's other cutters — often smaller, sometimes more precise, and easier to deliver. They exist because one enzyme can't do every job, and the 2025 patents show them being pointed at real therapies, not just the lab bench.