Mutation of the d-hordein gene by RNA-guided Cas9 targeted editing reducing the grain size and changing grain compositions in barley.

In this study, we successfully knock-out the d-hordein component of barley storage protein using RNA-guided Cas9. Mutation frequencies of 25% and 14% at two different target sites were obtained. Homozygous mutant plants that were T-DNA free were identified in the T generation.