A study published today by scientists from the Spanish National Cancer Research Centre (CNIO) describes how a genetic duplication that took place in the vertebrate ancestor some 500 million years ago encouraged the evolution of the ASF1b gene; a gene essential for proper cell division and related to some types of cancer such as breast cancer. The results of the study are published in Molecular Biology and Evolution. The conclusions of the study are the result of collaboration between the team led by Alfonso Valencia, Vice-Director of Basic Research and Director of CNIO’s Structural Biology & Biocomputing Programme, and the team led by Genevieve Almouzni, a member of CNIO’s Scientific Advisory Committee, at the Institut Curie in Paris, France. Valencia says that: "When proteins have such a close similarity as the one that exists between the two human copies of the ASF1 gene — ASF1a and ASF1b — it is commonly assumed that they have similar functions in cells; in this case related to fundamental processes such as DNA remodelling and repair, cell division, cell proliferation and genetic transcription or activation." The Genomic Environment, Key to Success in Separating Functions Almouzni’s team discovered several years ago that, despite the similarity in structure, the two copies of ASF1 were not redundant, but rather had divided up their ancestral functions…