A team of researchers at Cardiff University has discovered stem cells in the cheek can be used to supress the immune system. It should help patients with certain types of diabetes, and those whose bodies reject organs after transplants.
It'll be several years before a treatment's developed but the scientists say it's a real breakthrough.
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There will be long clear spells tonight, which will lead to a cold night for all.
Wales midfielder Joe Ledley has angrily denied accusations that he laughed at Seamus Coleman's horror injury in Dublin.
A dry, sunny and warm afternoon.