How to Edit Genes in Human Cells Using an Engineered CRISPR System

This patent describes an engineered CRISPR-Cas9 system for precisely cutting DNA in eukaryotic cells to change how genes work, opening the door for gene editing in complex organisms.

What it covers

This patent describes a method and system for altering the activity of specific genes within eukaryotic cells, which are cells with a nucleus, like human cells. It uses an "engineered, non-naturally occurring" CRISPR-Cas system. This system includes a "guide RNA" that acts like a GPS, directing a molecular scissor called a "Type-II Cas9 protein" to a specific target DNA sequence (Claim 1). Once the guide RNA finds its target, the Cas9 protein "cleaves the DNA molecule," meaning it cuts it. This cut then changes the "expression of the at least one gene product," either turning the gene down or off. For example, this system could be used to disable a faulty gene causing a genetic disease.

What it doesn't cover

• —Does not cover naturally occurring CRISPR-Cas systems found in bacteria, as the patent specifies "engineered, non-naturally occurring" systems.
• —Does not cover gene editing methods that use Cas proteins other than the "Type-II Cas9 protein" specified in the claims.
• —Does not cover altering gene expression in prokaryotic cells (like bacteria), as the claims specifically mention "eukaryotic cell."
• —Does not cover systems where the Cas9 protein and guide RNA are found together naturally, as the claims state they "do not naturally occur together."
• —Does not cover gene editing that doesn't involve *cleaving* the DNA molecule, as the claims explicitly state "the Cas9 protein cleaves the DNA molecule."

The clever bit

The core innovation was adapting the natural bacterial CRISPR defense system into an "engineered, non-naturally occurring" tool that could be programmed to cut specific DNA sequences in complex eukaryotic cells, like human cells, to alter gene expression.

Why it matters

This patent is a foundational piece of intellectual property for CRISPR-Cas9 gene editing in eukaryotic cells, including human cells. It enabled researchers to precisely modify genes in a wide range of organisms, accelerating scientific discovery and therapeutic development. The ability to target and cleave specific DNA sequences has revolutionized genetic research and holds immense promise for treating genetic diseases.

Real-world examples

• 1.Gene therapy research for genetic disorders
• 2.Development of disease-resistant crops
• 3.Basic biological research to understand gene function
• 4.Biopharmaceutical drug discovery