Cutting and Pasting Genes
Gene therapy has been an effective tool for treating many diseases, but some, such as HIV, brain cancer and Alzheimers Disease have proven more difficult to combat. Now new treatments are being tested that effectively cut out portions of DNA and fuse the pieces back together.
A Phase II clinical trial is currently underway in which a specific gene that’s necessary for HIV (CCR5) is removed and a mutation that’s resistant to the virus (delta32) is inserted. Early results indicate an increase in the modified cells and a corresponding decrease in HIV cells in the twelve subjects being tested.
In other research, similar techniques are being used to model certain diseases so that they can be studied in more detail. For example, models have been developed to target cystic fibrosis, sickle cell anemia, and autism, as well as hepatitis C, cholesterol, and insulin sensitivity. What used to take months and years to develop in animals can now be done in weeks using targeted genome editing.
For information: Srinivasan Chandrasegaran, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room 6402, Baltimore, MD 21205; phone: 410-614-2289; fax: 410-955-0617; email: schandra@jhsph.edu; Web site: www.jhsph.edu/about/
Feng Zhang, Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, NE-30-10055, 77 Massachusetts Avenue, Cambridge, MA 02139; phone: 617-714-7578; fax: 617-714-7698; email: zhang_f@mit.edu; Web site: www.mit.edu
