Children with severe combined immunodeficiency (SCID), or 'bubble boy' syndrome, can’t fend off even the weakest of germs. A rare genetic mutation means their bone marrow can’t produce crucial immune cells. These kids could die from a common cold, so they often have to live in isolated environments – or bubbles – to avoid infection. But now researchers have converted cells from SCID patients into stem cells (pictured) and corrected the mutation by editing 'misspelled' DNA. They used enzymes that act like molecular scissors, precisely snipping out and replacing one DNA letter in one gene. When the corrected cells matured in a dish, they produced natural killer cells, one of the missing weapons against infection, but not fully functional T cells. It’s hoped that one-day genetically corrected bone marrow cells could be transplanted back into SCID patients to generate the full arsenal of immune cells.
Written by Daniel Cossins
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