CRISPR-Cas9 technology to correct genetic disorders in embryos

Abstract

ABSTRACT: The discovery of the CRISPR/Cas system has provided scientist with an efficient, easy and site-specific method for gene editing. The main constraint in genetic modification was to create a double-stranded break in the DNA and to replace the mutated gene with the minimum possible off-target effects. Here, we systematically review the origin, function and uses of CRISPR-Cas9 technology for gene editing. The literature reviewed shows its uses are endless, from agricultural modifications to biotechnological applications. We also demonstrate CRISPR-Cas9’s potential with a case study in silico that replaces a mutated exon in the BRCA1 gene. This mutated exon is considered a pathogenic variant for hereditary breast and ovarian cancer and the idea is to correct it and prevent its transmission to the patient’s children. After identifying the genetic alteration that needs to be repaired, with the help of the corresponding online tools, we have designed highly specic guideRNAs (gRNA) and a corresponding donor. The selected gRNA, complementary to the target DNA sequence, guides the Cas9 protein to the desired location with a high ontarget efficacy and reduced off-target effects. This technology has raised many ethical concerns that should be taken into consideration and are being examined worldwide such as the possibilities for germline editing and its ecological impact.