Gene therapy was a 90s hit. The most promising medical advance of the decade was almost forgotten after some really serious side effects occurred in one clinical trial, but after nearly 3 decades a small trial in Germany has shown gene therapy not only to be safe for use in humans but also to have benefits for people suffering from achromatopsia, a type of colour blindness.
Although we are more acquainted with partial colour blindness, like that affecting red or green, achromatopsia is a full colour blindness, and patients can only see in monochrome. This problem is caused in at least one third of cases by a mutation in a single gene, namely the gene CNGA3. And it is against this gene that the gene therapy from the collaboration between the LMU in Munich and the University Hospital in Tübingen was targeted.
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