Thesis (Ph.D.) - Cairo University - Faculty of Veterinary Medicine - Department of Anatomy and Embryology

Myostatin gene (MSTN) is important because of its role in regulation of skeletal muscle growth in all vertebrates. In this study, CRISPR/Cas9 was utilized successfully to target channel catfish, Ictalurus punctatus, muscle suppressor gene MSTN. CRISPR/Cas9 induced high rates (88% - 100%) of mutagenesis in the target coding sites of MSTN. MSTN mutated fry had more muscle cells (p < 0.001) than controls, and the mean body weight of mutated fry increased by 29.7%. The nucleic acid alignment of the mutated sequences against the wild sequence revealed multiple forms of insertions and deletions. These results demonstrate that CRISPR/Cas9 is a highly efficient tool for editing the channel catfish genome, and open ways for facilitating channel catfish genetic enhancement and functional genomics. This approach can produce growth-enhanced channel catfish and increase productivity without introduction of unnatural genetic information or lengthy breeding programs

Issued also as CD