Better days ahead for farmers as gene editing offers hope for some food crops

By Joseph Maina

Kenya’s agriculture is set to benefit from several gene-editing projects that target some of the key food crops and livestock grown in the country.

Farmers of sorghum, maize, bananas, pigs and cattle and goats can expect good news from the ongoing research projects, that aim at improving disease resistance and building more robust crop and animal varieties.

Gene editing, also known as genome editing, is a set of advanced plant and animal breeding techniques that promise to produce high quality stock that can thrive in diverse ecological settings. Genome editing comprises a group of technologies that give scientists the ability to change an organism’s DNA. The technologies allow addition, removal or alteration of genetic material at particular locations in the genome.

A report titled “Genome Editing in Africa’s Agriculture 2021: An Early Take-off”, produced by the International Service for the Acquisition of Agri-biotech Applications (ISAAA) details some of the gene-editing projects underway in Africa.

Kenya is among three countries in the eastern African region that have ongoing projects in genome editing in agriculture, with eight scientists working on various projects. Uganda and Ethiopia are the other two.

One of Kenya’s gene editing projects seeks to build resistance in the sorghum plant against the parasitic striga weed.

The project, titled, Evaluation of Striga resistance in Low Germination Stimulant 1 (LGS1) mutant sorghum, is by Prof. Steven Runo, a professor of molecular biology at Kenyatta University. The project is evaluating LGS1 gene knock-out in conferring Striga resistance in sorghum. Striga is a huge constraint to production of sorghum and other cereal crops. Most cultivated cereals, including maize, millet, sorghum, and rice, are parasitized by at least one Striga species, leading to enormous economic losses.

Sorghum is an important crop in Kenya, and is mostly grown grown in western, northern Rift Valley, eastern and some parts of central region. The crop has a high local demand not only for food and fodder, but also in the brewing industry, which requires over 30,000 metric tonnes of white sorghum.

In another project, scientists are applying gene editing to control maize lethal necrosis, a disease that causes severe losses to maize in Kenya and neighbouring countries.  The project headed by Senior Research Scientist and Head of Maize Lethal Necrosis (MLN) Section James Kamau Karanja, will introduce resistance against MLN directly into parent inbred lines of popular commercial maize varieties, which are currently susceptible to the disease, and reintroduce them into the farmers’ fields in Kenya with possible scaling out to other countries in East Africa.

Goat farmers will also have a reason to smile as a gene-editing project promises a breakthrough in the control of trypanosomiasis, a notorious disease that has led to huge losses among livestock herders in Sub-Sahara Africa.

Scientists Dr Leena Tripathi, Jaindra Tripathi and Valentine Ntui are undertaking a CGIAR research program on roots, tubers and bananas. The project aims at To developing disease resistant varieties of banana.

Drought is among the major problems afflicting maize in Kenya. To help maize cope with drought is the focus of research by former post-doctoral fellow Dr. Elizabeth Njuguna. Her project is titled “Modulation of energy homeostasis in maize to develop lines tolerant to drought, genotoxic and oxidative stresses”, and seeks to broaden stress tolerance in plants by maintaining energy homeostasis during stress conditions. An expected outcome of the project is a maize variety that will be resistant to drought.

In another gene editing project, Dr Hussein Abkallo of ILRI is deploying CRISPR-Cas9 and synthetic biology technologies in developing vaccines against African Swine Fever Virus (ASFV) and East Coast fever (ECF).

These are two dangerous diseases affecting pigs and cattle, respectively.

CRISPR, which stands for “Clustered Regularly Interspaced Short Palindromic Repeats”, is a method in biological research that has many applications in agriculture. It has become an important tool in improving crops with disease and pest resistance, abiotic stress tolerance and improved nutritional content.

Elsewhere in Africa, scientists are using gene editing approaches to develop high yielding and disease resistant crops and livestock. In Ethiopia, a group of scientists is seeking to improve oil qualities of Ethiopian mustard (Brassica carinata) through application of CRISPR/CAS 9-based genome editing. A project in Uganda is applying targeted gene editing towards development of high yielding, stress resistant and nutritious crops, which include cassava, rice and maize.

Others include gene-editing research project in Egypt to produce drought tolerant wheat, and an investigation on the role of ANP32 proteins in the replication of Avian influenza Virus, which affects poultry, being conducted in Nigeria.

Gene editing differs from genetic modification (GM). Gene editing involves making a targeted, controlled change in the DNA of a living organism. Genetic modification involves removing a selected gene from one organism and randomly introducing it into another organism. The result of gene editing is quite exact and deliberate, while genetic modification may not promise similar exactitude in the end product.

Kenya is a market leader among African countries in this area of biotechnology. The country has begun drafting guidelines to regulate gene-edited products, applying procedures that have been formulated in Argentina.