One outcome of the Human Genome Project may be the development of gene therapy as a successful treatment modality. In fact, effective gene therapy may be a reality sooner than we think. Researchers in Boston have successfully transferred blood vessel-growing genes, identified before the Human Genome Project, to patients with inoperable heart disease-and those patients have dramatically reduced symptoms. This research is demonstrative of the kinds of gene therapy advances that may soon grow out of the work that Human Genome Project has done and continues to do.

Angina is chest pain that occurs because of decreased blood flow to the heart muscle. Blood flow is lowered when atherosclerosis or hardening of the arteries reduces the inner diameter of the coronary arteries so much that blood has difficulty passing. People with angina can have bypass surgery or angioplasty and stenting procedures when the blockages in their blood vessels are amenable. But for some patients, these techniques won't work. They take medications to relieve their symptoms. For still other patients, even drugs are ineffective, and they suffer what is called refractory, inoperable angina, that is "stubborn" angina that does not respond to standard treatments.

Cardiologists at St. Elizabeth's Medical Center in Boston, led by Dr. Jeffrey Isner, have pioneered a new treatment for people with this serious condition. They have transferred genes that code for growth factors directly to the patients' hearts and induced the growth of new blood vessels-blood vessels that carry oxygen-rich blood to the once-deprived heart muscle.

In a January 2001 report in the journal Anesthesia and Analgesia, Dr. Isner and his colleagues described 30 patients with refractory, inoperable angina who received direct injections of vascular endothelial growth factor (VEGF) into their heart muscle. One patient died five months after the procedure, but the other 29 experienced marked improvements in their symptoms. The frequency of their anginal episodes dropped from an average of 56 per week to fewer than four per week. Their need for nitroglycerine tablets dropped from an average of 60 tablets per week to just under three. Additional trials will explore if this hopeful beginning will yield a powerful and reliable therapeutic advance.

In these early trials using VEGF at least, scientists are beginning to develop techniques that may one day translate the theoretical work of the Human Genome Project from the laboratory bench to the bedside.