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An international collaboration of scientists was set up to understand the evolution of specific regions of human genome.. A team from the University's CERM (Research Center on Magnetic Resonances) and lead by Lucia Banci, has participated in the study coordinated by Howard Hughes Medical Institute/Department of Genome Sciences of the University of Washington (Seattle - USA) that has analysed the evolution of a locus of chromosome 16 – region p11.2 – extending the research not only to closely related primates, but also to archaic hominids, and the purpose was to understand better some aspects of human evolution.

The research appeared on the latest issue of Nature (“Emergence of a Homo sapiens-specific gene family and chromosome 16p11.2 CNV susceptibility”).

Scientists have investigated the manner in which the specific locus of chromosome 16 has evolved, presenting recurrent reorganisations and duplications. In particular, they have analysed the gene producing BOLA2 protein, as this latter is involved in various essential functions in all living organisms. The interest in this specific locus is due to the fact that duplications and cancellations inside it are the most common variations detected in case of autism related problems as well as being associated with other pathologies.

The comparative study, conducted on 2359 humans, 86 non-human primates, 3 archaic humans, 1 Neanderthal and 1 Denisova specimen proved that BOLA2 gene is duplicated in all examined Homo sapiens, including those belonging to Neolithic and Mesolithic populations, and in the most ancient archaic human among those examined, Ust’-Ishim (believed to have lived 45,000 years ago). Researchers have estimated that the duplication commenced around 282,000 years ago. In humans the number of copies of BOLA2 gene can range between 3 and 8 copies. On the other hand in non-human primates and in archaic hominids Neanderthal and Denisova there is only one copy of BOLA2.

"In the CERM laboratories, as Lucia Banci, professor of General and Inorganic Chemistry, explains, we have dealt with in vitrocharacterisation of the molecular mechanisms involved in BOLA2 and its partner, GRX3. The two proteins form one of the complexes functional to the assembly and transportation of the 2Fe-2S of proteins that bind it in order to carry out essential physiological processes, such as breathing and DNA repair. High concentrations of BOLA2 stimulate the production of a complex which is stable under oxidative conditions and the results of our analyses suggest that in the evolutionary process the expansion of the BOLA2 gene could have improved the efficiency of the maturation processes of Iron-Sulphur proteins in the presence of strong cellular oxidative stress.”