CRISPR-engineered genome editing for the next generation neurological disease modeling.

Neurological disorders often occur because of failure of proper brain development and/or appropriate maintenance of neuronal circuits. In order to understand roles of causative factors (e.g. genes, cell types) in disease development, generation of solid animal models has been one of straight-forward approaches. Recent next generation sequencing studies on human patient-derived clinical samples have identified various types of recurrent mutations in individual neurological diseases. While these discoveries have prompted us to evaluate impact of mutated genes on these neurological diseases, a feasible but flexible genome editing tool had remained to be developed. An advance of genome editing technology using the clustered regularly interspaced short palindromic repeats (CRISPR) with the CRISPR-associated protein (Cas) offers us a tremendous potential to create a variety of mutations in the cell, leading to "next generation" disease models carrying disease-associated mutations. We will here review recent progress of CRISPR-based brain disease modeling studies and discuss future requirement to tackle current difficulties in usage of these technologies.