Sir,  We are all enamoured by the amazing regenerative properties of stem cells.  Yet their use is not bioethically neutral.  As you report (News, December 6) they have long been used in bone marrow transplants – these are commonly referred to as ‘adult’ stem cells and are bioethically uncontroversial.  On the other hand, so-called ‘embryonic’ stem cells are controversial because they are harvested by destroying human embryos.

The treatment of stroke patients you describe used ‘CTX’ stem cells produced by the ReNeuron biotechnology company.  These were once advertised by ReNeuron as being ‘derived from non-embryonic human tissue’.  Indeed, that is true and they may therefore sound to be bioethically acceptable.  However, the fact is they were derived in 2003 from the cortex region of the brain of an aborted human foetus.

Sometimes medicine can shock us.

 

JOHN R LING

Author of Bioethical Issues

Aberystwyth