Generation of New Isogenic Models of Huntington's Disease Using CRISPR-Cas9 Technology

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by the expansion of CAG repeats in exon 1 of the huntingtin gene (HTT). Despite its monogenic nature, HD pathogenesis is still not fully understood, and no effective therapy is available to patients. The development of new techniques such as genome engineering has generated new opportunities in the field of disease modeling and enabled the generation of isogenic models with the same genetic background. These models are very valuable for studying the pathogenesis of a disease and for drug screening. Here, we report the generation of a series of homozygous HEK 293T cell lines with different numbers of CAG repeats at the HTT locus and demonstrate their usefulness for testing therapeutic reagents. In addition, using the CRISPR-Cas9 system, we corrected the mutation in HD human induced pluripotent stem cells and generated a knock-out of the HTT gene, thus providing a comprehensive set of isogenic cell lines for HD investigation.