Gábor Somlyai is a molecular biologist. Having finished his studies in 1982, he worked in the field of genetic engineering and gene mapping in Germany (1988 – Georg-August University, Göttingen) and in the USA (University of Missouri Columbia, Columbia). He was first inspired by Hungarian Nobel-prize winner Albert Szent-Györgyi, who believed that the true cause of cancer might be found at sub-molecular level. Somlyai began his investigations in 1990 with the examination of whether the naturally occurring deuterium – the heavy isotope of hydrogen – plays any role in the regulation of biological, i.e. intracellular molecular processes. His investigation was quite unique. The existence of deuterium has been known for nearly seventy years, and it is also known that it behaves differently from hydrogen and that in our body deuterium is present in 12-14 mmol/L concentration. Yet, nobody before had ever investigated the possible role of naturally occurring deuterium in living organism.