Cloning pioneer Hwang Woo-seok has successfully produced embryonic stem cells tailored to individuals in a major advance in the treatment of incurable diseases.

At a Thursday news conference in London, the professor said he harvested eleven stem cells from the body cells of patients suffering from immunodeficiency, diabetes and spinal cord diseases.

He cited no immune system rejection of the patients' cells as opposed to those from animals used as base cells. As a result, the success rate of his stem cell cultivation improved 15 times from prior experiments.

In an exclusive KBS interview, he said he passed four of seven major phases in one step before actualizing the practical use of stem cells.

On the biological ethics dilemma, Hwang said potential problems are preventable by complying with the country's rigorous life ethics law and seeking professional consultation.