Rice is a major staple food crop for over half of the global population. It is known for having white grains, but some varieties exhibit pigmented grains such as red rice. Red rice has high concentrations of healthful proanthocyanidins and anthocyanins. Two complementary genes (Rc and Rd) control the red coloration of rice grains. Wild rice species Oryza rufipogon has red grains, while most cultivated varieties have white grains due to a deletion in the Rc gene.
Scientists from Xiamen University and Fujian Academy of Agricultural Sciences used CRISPR-Cas9 to restore the deleted portion of the Rc gene. This successfully converted three elite white grain rice varieties into rice plants with red grains, producing high levels of proanthocyanidins and anthocyanidins. Furthermore, no significant change in major agronomic traits was observed in the mutants compared to the wild type, implying that restoring the Rc function had no effect on agronomic traits in rice.
Yiwang Zhu et al. 2019 CRISPR/Cas9‐mediated functional recovery of the recessive rc allele to develop red rice. Plant Biotechnology Journal. doi: 10.1111/pbi.13125
Source: Crop Biotech Update