Prokaryotes acquire virus resistance by integrating short fragments of viral nucleic acid into clusters of regularly interspaced short palindromic repeats (CRISPRs). Here we show how virus-derived sequences contained in CRISPRs are used by CRISPR-associated (Cas) proteins from the host to mediate an antiviral response that counteracts infection. After transcription of the CRISPR, a complex of C...

CRISPR (cluster of regularly interspaced palindromic repeats)/Cas and CRISPR/Cmr systems of Sulfolobus, targeting DNA and RNA respectively of invading viruses or plasmids are complex and diverse. We address their classification and functional diversity, and the wide sequence diversity of RAMP (repeat-associated mysterious protein)-motif containing proteins encoded in Cmr modules. Factors influe...

Cas9 is an RNA-guided double-stranded DNA nuclease that participates in clustered regularly interspaced short palindromic repeats (CRISPR)-mediated adaptive immunity in prokaryotes. CRISPR-Cas9 has recently been used to generate insertion and deletion mutations in Caenorhabditis elegans, but not to create tailored changes (knock-ins). We show that the CRISPR-CRISPR-associated (Cas) system can b...

The prokaryotic type II CRISPR/Cas9 system has been adapted to perform targeted genome editing in cells and model organisms. Here, we describe targeted gene deletion and replacement in human cells via the CRISPR/Cas9 system using two guide RNAs. The system effectively generated targeted deletions of varied length, regardless of the transcriptional status of the target gene. It is notable that t...

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system is an adaptive immune system in bacteria and archaea that has recently been exploited for genome engineering. Mutant mice can be generated in one step through direct delivery of the CRISPR/Cas9 components into a mouse zygote. Although the technology is robust, delivery remains a bottlene...

Manipulation of genomic sequences facilitates the identification and characterization of key genetic determinants in the investigation of biological processes. Genome editing via clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) constitutes a next-generation method for programmable and high-throughput functional genomics. CRISPR-Cas systems are readily r...

With the expansion of the microbiology field of research, a new genome editing tool arises from the biology of bacteria that holds the promise of achieving precise modifications in the genome with a simplicity and versatility that surpasses previous genome editing methods. This new technique, commonly named CRISPR/Cas9, led to a rapid expansion of the biomedical field; more specifically, cancer...

CRISPR (clustered regularly interspaced short palindromic repeats)-Cas9 (CRISPR-associated protein 9) is a revolutionary tool that utilizes an RNA-guided nuclease for efficient site-directed genome engineering in various eukaryotic systems. The double-strand breaks (DSBs) created by CRISPR-Cas9 are repaired in the cell by two predominant mechanisms: imprecise non-homologous end joining (NHEJ) a...

Molecular scissors engineered for site-specific modification of the genome hold great promise for effective functional analyses of genes, genomes and epigenomes and could improve our understanding of the molecular underpinnings of disease states and facilitate novel therapeutic applications. Several platforms for molecular scissors that enable targeted genome engineering have been developed, in...

After discovering the CRISPR-Cas9 as an extraordinary method for Gene editing it is necessary to reflect on the ethical, political and legal impact of this technology. This work pretends to offer a preliminary consideration of these problems. I do not pay attention to the potential of CRISPR-Cas9 in the fields of health or environment, nor to all the ethical, legal and political challenges it i...