The use of human embryonic material was controversial and so research into so-called therapeutic cloning was banned in many countries, including several states in the US. But years after the birth of Dolly, Japanese researchers built on Prof Wilmut’s work and found a way of creating cells that behaved in the same way as embryonic stem cells without using cloning, called Induced Pluripotent Stem Cells (IPS).
![Dolly the sheep creator Ian Wilmut dies aged 79 1 Dolly the sheep creator Ian Wilmut dies aged 79](https://i0.wp.com/ichef.bbci.co.uk/news/1024/branded_news/118C3/production/_131057817_h4230238-professor_ian_wilmut_with_dolly.jpg?fit=%2C&ssl=1)