During evolution, living species have adapted to environmental constraints according to the mechanism of natural selection; when a mutation that aids the survival (and reproduction) of an individual appears in the genome, it then spreads throughout the rest of the species until, after several hundreds or even thousands of generations, it is carried by all individuals. But does this selection, which occurs on a specific gene in the genome of a species, also occur on the same gene in neighboring species? On which set of genes has natural selection acted specifically in each species?
Researchers in the Dynamique et Organisation des Génomes team at the Institut de Biologie of the Ecole Normale Supérieure (CNRS/ENS/INSERM) have studied the genome of humans and three other primate species (chimpanzee, orangutan and macaque) using bioinformatics tools. Their work consisted in comparing the entire genomes of each species in order to identify the genes having undergone selection during the past 200,000 years. The result was that a few hundred genes have recently undergone selection in each of these species. These include around 100 genes detected in man that are shared by two or three other species, which is twice as many as might be anticipated as a random phenomenon. Thus a not inconsiderable proportion of the genes involved in human adaptation are also present in the chimpanzee, orangutan or macaque, and sometimes in several species at the same time. Natural selection acts not only by distancing different species from each other when new traits appear. But by acting on the same gene, it can also give rise to the same trait in species that have already diverged, but still have a relatively similar genome.
This study thus provides a clearer understanding of the group of genes that are specifically implicated in human evolution (during the past 200,000 years), as it allows the identification of those genes which did not undergo selection in another primate line. An example that has been confirmed by this study is the well-known case of the lactase gene that can metabolize lactose during adulthood (a clear advantage with the development of agriculture and animal husbandry). The researchers have also identified a group of genes involved in some neurological functions and in the development of muscles and skeleton.
Janos Haits on 02 Apr 12Come work with us Interested in working with researchers from different disciplines within the Harvard, MIT and Broad community and an unique opportunity to participate in world-class research to make an impact on human health? Come work with us! We are looking for a computational biologists to handle data from a wide variety of experimental methods, focusing on next-gen sequencing technologies. Keep Reading... SCDE is live The Stem Cell Discovery Engine (SCDE) is an integrated platform that allows users to consistently describe, share and compare cancer and tissue stem cell data. It is made up of an online database of curated experiments coupled to a customized instance of the Galaxy analysis engine with tools for gene list manipulation and molecular profile comparisons. The SCDE currently contains more than 50 stem cell-related experiments. Each has been manually curated and encoded using the ISA-Tab standard to ensure the quality of the data and its annotation. Keep Reading... The Center for Health Bioinformatics at the Harvard School of Public Health provides consults to researchers for the management, integration and contextual analysis of biological high-throughput data. We are a member of the Center for Stem Cell Bioinformatics, the Environmental Statistics and Bioinformatics Core at the Harvard NIEHS Center for Environmental Health and the Genetics & Bioinformatics Consulting group for Harvard Catalyst and work closely with our colleagues in the Department of Biostatistics and the Program in Quantitative Genomics to act as a single point of contact for computational biology,
