As of February 2016, the United States had no regulations governing mitochondrial donation, and Congress barred the FDA from evaluating any applications that involve implanting modified embryos into a woman.
The United Kingdom became the first country to legalize the procedure: the UK's chief medical officer recommended it be legalized in 2013; parliament passed The Human Fertilisation and Embryology (Mitochondrial Donation) Regulations in 2015, and the regulatory authority published regulations in 2016.