Crop Biotech Update

A High-Efficiency CRISPR-Cas9 System for Targeted Mutagenesis in Cotton

March 8, 2017

The complex allotetraploid genome is one of the major challenges for repressing gene expression in cotton. Hence, developing a site-specific DNA mutation is a dream for cotton breeders. The CRISPR-Cas9 system is a robust technique for targeted-DNA mutation. Using the CRISPR-Cas9 system, Chao Li from East Carolina University designed two sgRNAs, GhMYB25-like-sgRNA1 and GhMYB25-like-sgRNA2, for direct Cas9-mediated allotetraploid cotton genome editing.

High proportions of CRISPR-Cas9-induced specific truncation events, either from GhMYB25-like A DNA site or from GhMYB25-like D DNA site, were detected in 50% of the examined edited cotton. Further analysis also revealed that 100% and 98.8% mutation frequency occurred on GhMYB25-like-sgRNA1 and GhMYB25-like-sgRNA2 target sites, respectively. All examined samples had no off-target-caused mutation events.

These results demonstrate that CRISPR-Cas9 can be used to generate DNA level mutations on allotetraploid cotton genome.

For more information, read the article in Nature.