On January 14, 2001 the British government passed The Human Fertilisation and Embryology (Research Purposes) Regulations 2001[50] to amend the Human Fertilization and Embryology Act 1990 by extending allowable reasons for embryo research to permit research around stem cells and cell nuclear replacement, thus allowing therapeutic cloning. However, on 15 November 2001, a pro-life group won a High Court legal challenge, which struck down the regulation and effectively left all forms of cloning unregulated in the UK. Their hope was that Parliament would fill this gap by passing prohibitive legislation.[51][52] Parliament was quick to pass the Human Reproductive Cloning Act 2001 which explicitly prohibited reproductive cloning. The remaining gap with regard to therapeutic cloning was closed when the appeals courts reversed the previous decision of the High Court.[53]
The first licence was granted on August 11, 2004 to researchers at the University of Newcastle to allow them to investigate treatments for diabetes, Parkinson's disease and Alzheimer's disease.[54] The Human Fertilisation and Embryology Act 2008, a major review of fertility legislation, repealed the 2001 Cloning Act by making amendments of similar effect to the 1990 Act. The 2008 Act also allows experiments on hybrid human-animal embryos