Biotechnology researchers from the Chinese Academy of Sciences have successfully developed a strain of wheat with no genes added from outside and it is resistant to the damaging powdery mildew fungus.

Powdery mildew is a deadly fungus which can damage large stocks of wheat and is prevalent all over the world.

The Chinese team was headed by Caixia Gao and it developed this strain of wheat by basically removing genes. A gene is a stretch of DNA that codes for a specific protein which is something that is advantageous for the plant in this case.

The language of genes and nucleic acid is almost universal and it hardly matters where a gene originates from. It will be read in the same way in the cells of the plant as long as it is inserted correctly.

The researchers chose the mildew-resistance locus gene for the purpose along with a couple of tools -TALEN and CRISPER. They introduced targeted mutations which resulted in stopping the work of the mildew-resistance locus gene. This gene was removed from genetic code of the wheat in effect.

How exactly does breaking a gene make a plant resistant to the disease? The mildew-resistance locus is a regulator gene which is not involved in fighting pathogens. When mildew-resistance locus is expressed, the genes that
combat infections are repressed and this is known as down regulation.

During the course of the research, the researchers have applied some innovative techniques in order to attain these results. Bread wheat is hard to change since it is a hexaploid organism. This means that it has six copies of its chromosomes for three versions of its entire genes.

If you intend to modify the genes of wheat, you have to get to all the three copies of a gene, else it will still be active in the plant.