Sir, – Several moral and ethical questions are being raised by a life-saving medical innovation in the US with the implantation of a genetically modified pig's heart in a 57-year-old heart patient (World, January 11th). It is an amazing achievement of medical science that could bring a revolution in the field of surgery. However, we must not forget the importance of organ donation by humans. It is the ultimate gift one could bestow on another human being. – Yours, etc,
CHANDER SANGRA,
Lucan,
Co Dublin.