In rice (Oryza sativa), the amylose content is controlled by a single
dominant Waxy gene. The team of Jinshan Zhang from the Chinese Academy of
Sciences used CRISPR-Cas9 to introduce a loss-of-function mutation into the
Waxy gene in two widely-cultivated elite japonica varieties.
The mutations brought about by CRISPR-Cas9 in the Waxy gene reduced the
amylase content of the rice, converting it into a glutinous one without
affecting other desirable agronomic traits. The team was also successful in
removing transgenes from the progeny of these genome-edited lines.
The success of CRISPR-Cas9 in inducing mutations in the Waxy gene of rice
could offer an effective and easy strategy to improve glutinosity in elite
rice varieties. This study also provides an example of generating improved
crops with potential for commercialization, by editing a gene of interest
directly in elite crop varieties.