How genetic modification techniques in crop improvement have evolved

Genetically modified wheat. FILE PHOTO | POOL

Crop improvement through genetic modification is as old as mankind. Our nomadic ancestors domesticated plants through selection 10,000 years ago.

The domestication involved selecting individual plants with the most desirable characteristics (traits) – such as palatability, yield, reduced toxicity, size of seeds or fruits etc. – for continued propagation.

Selection permitted humans to domesticate numerous wild plants into crops such as wheat, rice, maize, potato, and tomato among others.

Read: Scientists’ plan to build confidence around GMOs

This old selection method has been enhanced with modern methods that help create a genetic variation or that use molecular analysis to detect plants likely to express desired features.

Then plant breeders discovered how to deliberately change the expression of traits in plants by crossing – through pollination – specific parent plants that are sexually compatible, producing a hybrid that carries genes from both parents.

Through crossing, breeders combine the useful characteristics of the two parent plants – they may add a disease-resistant gene from one plant to another that is high yielding but disease-susceptible.

However, crossing, which is the mainstay of modern plant breeding, relies on nature’s random process of recombining genes and transfers thousands of unknown genes with unknown functions along with the desired genes.

Because this method of recombining genes is random, breeders must make hundreds or thousands of hybrid offspring to create and identify those few that possess useful features with a minimum of undesirable traits, a process that is fraught with inefficiencies.

Consequently, the crossing and selection process to develop a new crop variety may take 10 years.

Then came GM technology, which resulted in what we commonly refer to as GMOs. In this recent breeding technique genes derived from unrelated species are inserted into an organism, which was hitherto not possible.

And now, in genome editing, a section of a plant’s genetic makeup can be added, removed, or replaced in a precise manner.

These newer modern techniques do nothing more than speed up the process of getting beneficial changes to appear in plants.

Read: Scientists campaign for worldwide use of GM crops

The aim of all these breeding tools is the same, and there is universal scientific consensus on the adequacy of the safety processes.