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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Cloudy with outbreaks of patchy light rain at times, particularly across central and southern parts.
Wales are looking for a new manager after Chris Coleman resigned in order to take the vacant job at Sunderland.
Hallie Evans is wearing a purple dress and has long blonde hair.