(March 21, 2008) – There is a cool article in today’s ScienceDaily reporting a successful attempt to prevent Menkes Disease by reversing a genetic defect before birth. You can read the full article by clicking here, Deadly Genetic Disease Prevented Before Birth In Zebrafish.
JR
By injecting a customized “genetic patch” into early stage fish embryos, researchers at Washington University School of Medicine in St. Louis were able to correct a genetic mutation so the embryos developed normally.
The research could lead to the prevention of up to one-fifth of birth defects in humans caused by genetic mutations, according to the authors.
Erik C. Madsen, first author and an M.D./Ph.D. student in the Medical Scientist Training Program at Washington University School of Medicine, made the groundbreaking discovery using a zebrafish model of Menkes disease, a rare, inherited disorder of copper metabolism caused by a mutation in the human version of the ATP7A gene. Zebrafish are vertebrates that develop similarly to humans, and their transparency allows researchers to observe embryonic development.Children who have Menkes disease have seizures, extensive neurodegeneration in the gray matter of the brain, abnormal bone development and kinky, colorless hair. Most children with Menkes die before age 10, and treatment with copper is largely ineffective.
The development of organs in the fetus is nearly complete at a very early stage. By that time, the mutation causing Menkes disease has already affected brain and nerve development.
The genetic mutations Madsen and the researchers worked with are caused by splicing defects, or an interruption in genetic code. The morpholinos prevent that interruption by patching over the defect so the gene can generate its normal product.
“Consider the genetic code as a book, and someone has put in random letters or gibberish in the middle of the book,” Madsen said. “To be able to read the book, you have to ignore the gibberish. If we can make cells ignore the gibberish, or the splicing defect, the fetus can develop normally.”Up to 20 percent of genetic diseases are caused by splicing defects, Madsen said, so this treatment method could potentially be used for many other genetic diseases.
