New CRISPR Experiment Corrects Clotting in Mice

The future of gene editing is slowly approaching great promise. Recent developments surrounding CRISPR/Cas9 showed its efficiency and promise in correcting disease-causing mutations. For the first time, it was used to develop a dual gene therapy to treat hemophilia B in mice, which normally leads to a defective clotting protein.

Scientists from the Perelman School of Medicine at the University of Pennsylvania has developed a dual gene therapy approach to deliver key components of a gene created by CRISPR/Cas9 to treat hemophilia B. 

It may be important to remember that CRISPR is a revolutionary gene editing method that met criticisms due to its potential. 

Most single-gene diseases such as hemophilia are caused by different mutations scattered in a specific gene rather than a single predominant mutation. This means a vector must be made applicable for patients with any mutations.

The study turned into a pre-clinical "proof of concept" with the help of CRISPR/Cas9 gene-targeting approach.

According to Science Daily, the CDC said hemophilia occurs in approximately one of 5,000 live births and about 20,000 people are with hemophilia in the U.S. alone.

First author Lili Wang said that their method cured the mice they were using for the study. Her team performed the experiment in a mouse model in which the clotting factor gene was knocked out. They used CRISPR to specifically target a region in the genes to directly deliver them to mouse's liver cells. 

The injection of the two vectors in newborn and adult mice showed significant improvement over the course of four months. When they were given a partial liver removal, they all survived the procedure without complications or interventions.

This proves the potential of CRISPR as a method of in vivo genome editing not just for conditions such as hemophilia but potentially other diseases as well.