Individuals with genetic disorders can be treated by using their own reprogrammed and corrected cells, say scientists from the Morgridge Institute for Research.
The finding carries potential applications in gene therapy treatments for Huntington's disease, degenerative retinal disease or diabetes.
The researchers found that the process of correcting a genetic defect does not substantially increase the number of potentially cancer-causing mutations in induced pluripotent stem cells.
Their work suggested that human induced pluripotent stem cells altered to correct a genetic defect might be cultured into subsequent generations of cells that remain free of the initial disease.
However, although the gene correction itself does not increase the instability or the number of observed mutations in the cells, the study reinforced other recent findings that induced pluripotent stem cells themselves carry a significant number of genetic mutations.
"This study showed that the process of gene correction is compatible with therapeutic use," said Sara Howden, primary author of the study, who serves as a postdoctoral research associate in James Thomson's lab at the Morgridge Institute for Research.
"It also was the first to demonstrate that correction of a defective gene in patient-derived cells via homologous recombination is possible," she said.
In the study, the researchers used a technique called episomal reprogramming to generate the induced pluripotent stem cells.
The technique allowed them to produce cells that were free of potentially harmful transgene sequences.
The scientists then corrected the actual retinal disease-causing gene defect using a technique called homologous recombination.
The stem cells were extensively "characterized" or studied before and after the process to assess whether they developed significant additional mutations or variations.
The results showed that the culture conditions required to correct a genetic defect did not substantially increase the number of mutations.
"By showing that the process of correcting a genetic defect in patient-derived induced pluripotent cells is compatible with therapeutic use, we eliminated one barrier to gene therapy based on these cells," said Howden.
The study is published in the online edition of the journal Proceedings of the National Academy of Sciences. (ANI)