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• Another Gene Discovered, Another Step Closer to A Cure

• HairSite Editorials - 10/5/99

• Weill Medical College, Cornell University

Keywords: Gene Therapy; "Hairless" Gene; Sonic Hedgehog Gene; Liposome

Dr. Christiano of Columbia University, New York,   stunned the world in January 98 when she announced the discovery of the "hairless" gene. Now in a little more than a year's time, another big discovery in gene therapy was announced by Weill Medical College of Cornell University.

The discovery is based on experiments involving a gene that is essential for hereditary cell developments and growth, called Sonic Hedgehog. The clinical study was conducted by Dr. Ronald G. Crystal who led the group of gene therapists at Cornell University.

The study was performed on mice whose hair follicle had gone into a normal resting phase, similar to what humans would experience from time to time. The mice were then given an injection of the Sonic Hedgehog gene and in just a few days, the resting or dormant hair follicles were converted into the growth phase. To facilitate comparison and to monitor the results of the experiement, the mice's fur (black in color) was bleached blond prior to the injection. In just a matter of days after the injection, researchers observed new black hair started to grow on the mice. The delivery mechanism used in the experiment was a kind of virus, although some had previously suggested that liposome, a commonly used carrier or delivery mechanism for cosmetics and skin care, may also be a good candidate to transport the gene to targeted follicles.

While the results were promising on mice, nothing in that nature has been tried on humans at this point. Some suggested that a similar treatment on humans would probably require multiple injections over the scalp to be effective. According to Dr. Ervin Epstein, University of California, San Francisco, future developments may involve combining the Sonic Hedgehog gene in a concoction of hair stimulant agents to make hair growth.

However, there are still obstacles ahead. Most important is the fact that the overactive nature of the Sonic Hodgehog gene can cause certain kinds of skin cancer on the patients.

Compared to the "hairless" gene discovered by Dr. Christiano, the Sonic Hodgehog gene injection may have a wider application to hair loss sufferers. The "hairless" gene is mostly limited to a very rare condition in which people quickly lose their hair, including eyelashes and eyebrows and never grow back. 

The clinical experiment was reported in the latest issue of The Journal of Clinical Investigation.

For previous coverage on Gene Therapy, please check out:
-Nude- Gene - A Step Closer to Gene Therapy
 DR. CHRISTIANO  - REPORT ON GENE MAPPING
HAIR LOSS GENE DISCOVERED

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• GENE THERAPY