Of all the big, world-remaking bets on the genome-editing tool known as Crispr, perhaps none is more tantalizing than its potential to edit some of humanity’s worst diseases right out of the history books.
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The major concern is that an army of DNA-breaking enzymes might sometimes wander astray and cause unintended mutations in places it shouldn’t.
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Using a new method for measuring unplanned edits, a team of American, Chinese, and European scientists has found that the same base editor, widely in use by researchers today, actually messes up the genome at an eyebrow-raising rate.
Their report, published [February 28] in Science, claims a 20-fold increase in mutations over what would be expected in the normal course of cell division and repair in mouse embryos.
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The question on [researcher Steve] Murray’s mind now is, how many errors are too many? Cells are prone to making their own mistakes—on the order of once every million to 100 million base pairs… . Does it matter if an overactive gene editor makes that number closer to one in 500,000? … What if the mistake in that one cell grows into a cancer? And if a patient is on death’s door, how much does it matter?
Read full, original post: Gene editing is trickier than expected – but fixes are in sight
