The only other research team to have successfully cloned human embryos has quarrelled and split up in a dispute about unprofessional self-promotion. Two professors at the University of Newcastle, Professor Miodrag Stojkovic, a stem cell biologist, and Professor Alison Murdoch, an IVF specialist who is head of the British Fertility Society, have fallen out over her orchestration of the announcement of their breakthrough research last May. She ensured that it would coincide with the day that Hwang's paper was published.

The Newcastle team's announcement was criticised at the time by the journal Nature as "contrary to good scientific practice". It had breached convention by publicising results before its research had been peer-reviewed and published in full in a scientific journal. An incensed Professor Stojkovic claims that he had not agreed to this plan.

Professor Stojkovic also claimed that he deserved the lion's share of the credit for their research. "There are plenty of people dissatisfied with Professor Murdoch taking the publicity," he said. The laboratory scientists do not need someone who has been doing nothing in the laboratory and who knows nothing about the work to represent them." Stojkovic has now moved to a research institute in Valencia, Spain.