Now University of Florida researchers may be one step closer to finding a safe way to spur production of this missing protein in patients with the most common form of the hereditary bleeding disorder. Using a dormant strand of DNA that has quietly existed in fish for millions of years, the researchers replaced the faulty gene responsible for the disease in neonatal mice, according to findings published online this month in the journal Molecular Therapy.
"The degree to which these patients have problems from hemophilia stems from how much of this protein, factor VIII, is missing," said Bradley Fletcher, M.D., Ph.D., a UF assistant professor of pharmacology and one of the lead authors of the study. "If they have very low levels of it, they have lifelong problems of bleeding, but what's even more problematic for them is they bleed into their joints, knees, hips and ankles, which limits their mobility."
Although hemophiliac mice don't develop some of these more extreme symptoms of the disease, gene therapy prevented profuse bleeding in the animals, the findings show.
More than 18,000 Americans, nearly all men, have hemophilia A, the most common form of the disease, according to the Centers for Disease Control and Prevention. Currently, the only safe treatment for the disorder is a purified form of the protein, but it can cost patients thousands of dollars and its effects don't last long. Scientists have been trying to find a safe way to perform gene therapy in hemophilia patients for years, but problems with the viruses typically used to transport needed genes to their target destinations have stymied their success, Fletcher said.
Researchers usually hide corrective genes inside viruses, which then infect cells. Without the virus to act as a key, the gene would be unable to enter the cell. But
Source:University of Florida