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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ITV Cymru Wales will publish the final poll of the Welsh Assembly Election 2016 campaign on Wednesday this week.
A mostly cloudy day with outbreaks of light rain and drizzle at times, mainly over the mountains where it could occasionally turn heavy.
The parents of a young boy from Anglesey say they're determined to find a missing dog that was bought to aid his recovery from surgery.