The witness told the court that several samples taken using sticky tape to pick up skin cells showed a mixture of DNA from two or three individuals.

BBC: Lynda Spence

Coley's technology takes aim at toll-like receptors (TLRs), detectors on immune system cells that pick up invaders and bad actors in the body.

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And the pattern is inconsistent - pick a bunch of neighbouring cells and they could each have different chromosome counts.

BBC: Thriving cancer's 'chaos' explained

Exactly what happens to the windpipe after it is transplanted isn't clear, but researchers believe that placing stem cells, which are capable of developing into different types of body cells, can pick up signals from their environment and integrate with existing tissues.

CNN: Toddler gets new windpipe from her own stem cells

Genzyme, he says, has its pick of the viruses that are used to insert genes into cells.

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