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It’s made up of a genetic network integrated into human cells, encased in an implantable device. When this is inserted under the skin, it constantly checks the calcium levels in a person’s blood. High calcium levels are an early biomarker for four of the most common kinds of cancer – prostate, lung, colon and breast.
When the implant detects elevated calcium levels for a prolonged period of time, it triggers the genetically-modified cells to begin producing extra melanin. This pigment is what darkens skin to form freckles and moles, creating a clearly-visible signal at the site of the implant, telling the person that something is wrong and they should visit a doctor. The mole will appear long before the cancer could normally be detected through other means.
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With further research, the team says the concept could be adapted to monitor other biomarkers besides calcium, to serve as early warning systems for other gradually-developing illnesses like neurodegenerative diseases and hormonal disorders. Unfortunately, a publicly-available device is still at least a decade away.
Read full, original post: Implant gives early cancer warning by growing an artificial mole on your skin