June 27, 2011

Scientists Alter Genetic Code In Mice

Scientists have managed to "edit" the genetic code for the first time in a living animal.

The researchers altered cells in mice to repair a faulty gene, which was responsible for the blood clotting disorder hemophilia.

The team used an innovative gene therapy technique called genome editing, which hones in on the precise location of mutated DNA.

Scientists used two version of a genetically engineered virus in this study, one carrying enzymes that cut DNA in an exact spot and one carrying a replacement gene to be copied into the DNA sequence. 

"Our research raises the possibility that genome editing can correct a genetic defect at a clinically meaningful level after in vivo delivery of the zinc finger nucleases," Katherine A. High, M.D., a hematologist and gene therapy expert at The Children's Hospital of Philadelphia and the study leader, said in a statement.

High's research makes use of genetically engineered enzymes called zinc finger nucleases (ZFNs) that act as molecular word processors, editing mutated sequences of DNA. 

A new gene could then be inserted in the right place and the DNA could be made to reform around it.

A third of genetic deceases are caused by a single faulty gene.

High said she plans to test the treatment on larger animals.

"We need to perform further studies to translate this finding into safe, effective treatments for hemophilia and other single-gene diseases in humans, but this is a promising strategy for gene therapy," she said in a statement.

The study was published in the journal Nature.


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