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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Andrew Price joins South Wales Caving Club to venture into the deepest cave in the UK
Any drizzle this afternoon will subside to leave a largely dry evening. Clearer skies in the north overnight.
Police were called to several Tesco stores in Wales to deal with chaos at midnight. Huge numbers hunted for bargains in shops and online.