Somos lo que somos porque somos virus y bacterias: el impacto de los microorganismos endógenos en la biología del huésped

Abstract

The advent of whole-genome sequencing combined with an enhanced of bioinformatics techniques, allow us the accuracy detection of microbial DNA sequences into the genome of several animals, including human genome. Throughout millions of years, these endogenous “microorganisms” have contributed to the evolution of the host genomes by introducing innovation and genetic variation, and influencing the host gene expression. In particular, the endogenous retroviruses have an essential role on host biology: they have been linked to various human diseases; they take part in the formation of the placenta and in embryonic development; they can protect the host against exogenous viral infections; and even they had an essential role in human evolution. In addition to endogenous retroviruses, recently it has been suggested that gene acquisition through horizontal gene transfer between different species has also contributed to animal evolution.