Gut microbiota in gastrointestinal diseases.

Gut microbiota is a highly dense population of different kinds of bacteria residing in the gut which co-evolves with the host. It engages in a number of metabolic and immunological activities. Gut microbiota is associated with maintenance of health, and unbalanced microbiota contributes in the development of several diseases. Alteration of beneficial gut microbiota population triggers gastrointestinal diseases including irritable bowel syndrome, inflammatory bowel disease, celiac disease, colorectal cancer, and many others. Gut microbiota can be affected by multiple factors such as diet, stress, genetic variations. In this chapter, we highlight how gut microbiota plays a key role in pathogenesis of gastrointestinal disease.

Current approaches in CRISPR-Cas9 mediated gene editing for biomedical and therapeutic applications.

A single gene mutation can cause a number of human diseases that affect the quality of life. Until the development of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein (Cas) systems, it was challenging to correct a gene mutation to avoid a disease by reverting phenotypes. The advent of CRISPR technology has changed the field of gene editing, given its simplicity and intrinsic programmability, surpassing the limitations of both zinc-finger nuclease and transcription activator-like effector nuclease and becoming the method of choice for therapeutic gene editing by overcoming the bottlenecks of conventional gene-editing techniques. Currently, there is no commercially available medicinal cure to correct a gene mutation that corrects and reverses the abnormality of a gene's function. Devising reprogramming strategies for faithful recapitulation of normal phenotypes is a crucial aspect for directing the reprogrammed cells toward clinical trials. The CRISPR-Cas9 system has been promising as a tool for correcting gene mutations in maladies including blood disorders and muscular degeneration as well as neurological, cardiovascular, renal, genetic, stem cell, and optical diseases. In this review, we highlight recent developments and utilization of the CRISPR-Cas9 system in correcting or generating gene mutations to create model organisms to develop deeper insights into diseases, rescue normal gene functionality, and curb the progression of a disease. Delivery of CRISPR-components being a pivotal aspect in proving its effectiveness, various proven delivery systems have also been briefly discussed.