CRISPR-Cas9 is a valuable tool for research and has been widely applied to
different plant species. However, the efficiency of this method is not
available for the allotetraploid rapeseed (Brassica napus), an important
oilseed crop. Huazhong Agricultural University researchers evaluated the
mutation efficiency of the CRISPR-Cas9 for 12 genes in rapeseed, including
paralogous genes.

CRISPR efficiently induced targeted mutations both for single locus and
multiple loci targeting in rapeseed. CRISPR also induced mutations in
paralogous genes, or different genes with the same function in a species.
Since the paralogous genes in rapeseed have highly similar sequences, they
were successfully targeted using only a single sgRNA. No off-target
mutations were identified in the CRISPR-Cas9 lines, indicating that the
mutations induced were highly specific.

Half of the mutations, including homozygotes, bi-alleles, and heterozygotes
were also stably inherited in the next generation (T1) without any new
mutations or reversions.These results demonstrate that CRISPR-Cas9 can be an
efficient tool for targeted genome modifications at multiple loci in
rapeseed.

[www.ncbi.nlm.nih.gov]