The Challenge of CRISPR-Cas Toward Bioethics.

Since determining the structure of the DNA double helix, the study of genes and genomes has revolutionized contemporary science; with the decoding of the human genome, new findings have been achieved, including the ability that humans have developed to modify genetic sequences in vitro. The discovery of gene modification mechanisms, such as the CRISPR-Cas system (Clustered Regularly Interspaced Short Palindromic Repeats) and Cas (CRISPR associated). Derived from the latest discoveries in genetics, the idea that science has no limits has exploded. However, improvements in genetic engineering allowed access to new possibilities to save lives or generate new treatment options for diseases that are not treatable by using genes and their modification in the genome. With this greater knowledge, the immediate question is who governs the limits of genetic science? The first answer would be the intervention of a legislative branch, with adequate scientific advice, from which the logical answer, bioethics, should result. This term was introduced for the first time by Van Rensselaer Potter, who in 1970 combined the Greek words bios and ethos, Bio-Ethik, which determined the study of the morality of human behavior in science. The approach to this term was introduced to avoid the natural tension that results from the scientific technical development and the ethics of limits. Therefore, associating the use of biotechnology through the CRISPR-Cas system and the regulation through bioethics, aims to monitor the use of techniques and technology, with benefits for humanity, without altering fundamental rights, acting with moral and ethical principles.

Analysis of CRISPR-Cas systems in Gardnerella suggests its potential role in the mechanisms of bacterial vaginosis.

Bacterial vaginosis (BV) is the principal cause of vaginal discharge among women, and it can lead to many comorbidities with a negative impact in women's daily activities. Despite the fact that the pathophysiological process of BV remains unclear, great advances had been achieved in determining consequences of the shift in the vaginal community, and it was defined that Gardnerella spp., plays a key role in the pathogenesis of BV. Interactions of vaginal phage communities and bacterial hosts may be relevant in eubiosis/dysbiosis states, so defense mechanisms in Gardnerella spp., against phage infections could be relevant in BV development. In this study, we analyzed CRISPR-Cas systems among the 13 Gardnerella species recently classified, considering that these systems act as prokaryotic immune systems against phages, plasmids, and other mobile genetic elements. In silico analyses for CRISPR-Cas systems mining over the 81 Gardnerella spp., strains genomes analyzed led to the identification of subtypes I-E and II-C. Spacers analyses showed a hypervariable region across species, providing a high resolution level in order to distinguish clonality in strains, which was supported with phylogenomic analyses based on Virtual Genomic Fingerprinting. Moreover, most of the spacers revealed interactions between Gardnerella spp., strains and prophages over the genus. Furthermore, virulence traits of the 13 species showed insights of potential niche specificity in the vaginal microbiome. Overall, our results suggest that the CRISPR-Cas systems in the genus Gardnerella may play an important role in the mechanisms of the development and maintenance of BV, considering that the Gardnerella species occupies different niches in the vaginal community; in addition, spacer sequences can be used for genotyping studies.