[1] He made headlines in September 2016 for successfully producing the world's first three-parent baby using the spindle transfer technique of mitochondrial replacement.
[4] John Zhang studied at the Zhejiang University School of Medicine in China, and graduated with an MD in 1984.
[6] In 2003, while working with researchers at the Sun Yat-Sen University of Medical Science, Zhang experimented with a mitochondrial donation technique called pronuclear transfer to help a Chinese woman who had a fertility problem.
He extracted only the young nuclei (pronuclei) from the mother and her husband, and introduced them into the host egg cell,[7] hence the popular name "three-parent baby".
[10] In order to help a woman in Mexico who had a genetic-neurological trait called Leigh syndrome, Zhang used the spindle transfer technique in 2015.
There is also opposition to the nuclear transfer method due to the waste of embryos, or potential risk to children born by the technique.
"[16] Sian Harding, a member of the British Nuffield Council on Bioethics and the Scientific Advisory Board of the PPP "Stem Cells for Safer Medicines", also defended Zhang, saying that there was no deliberate destruction of embryos, and said, "It's as good as or better than what we'll do in the UK.
"[17] As of 2019, his affiliations with scientist He Jiankui has been questioned in regards to his involvement and knowledge of the gene edited babies, Lulu and Nana.
It was reported that Zhang intended to open a medical tourism business in Hainan for gene-edited babies.
He is a consultant for Reproductive Nuclear Transfer and Stem Cell Research, Cellular Reconstruction and the Special Programme of Therapeutic Cloning at Sun Yat-sen University, Guangzhou.
He is also a consultant for the IVF and Gamete Laboratory at the Fertility Centre of Wenzhou Medical College, Zhejiang Province, China.