A New Field of Medicine
Genome editing makes permanent changes to the genetic code of a cell by correcting, disabling or modifying the DNA. Genome editing works by using enzymes called “engineered nucleases” that act like molecular scissors. By cutting DNA at a precise spot in the genome, DNA can be removed, added or replaced for therapeutic effect. The goal of genome editing is to provide a permanent therapeutic solution or cure for genetic diseases.
Using Zinc Finger Nucleases to Edit the Genome
Sangamo leads the therapeutic genome editing field, with multiple clinical trials underway in the United States. Our zinc finger nuclease (ZFN) technology is based on a naturally occurring class of proteins called zinc finger DNA-binding proteins (ZFPs) which recognize and bind to specific sequences of DNA. We engineer ZFNs for precision, efficiency and specificity, which we believe are the critical parameters for a therapeutic genome editing technology.
Currently being evaluated in clinical trials for the treatment of MPS I, MPS II and hemophilia B, our in vivo genome editing approach packages ZFNs and a therapeutic transgene in AAV vectors for delivery to liver cells. The ZFNs make a double stranded break in the DNA in a precise location in the albumin gene, where the transgene is permanently integrated using the cell’s natural repair mechanism.
Advantages of ZFNs for designing genome editing therapeutics
- Precision: Ability to target any desired nucleotide in the human genome
- Efficiency: Level of editing at the desired target nucleotide or sequence
- Specificity: Editing the target nucleotide or sequence without editing anywhere else in the genome