Introduction of GE animals doesn’t guarantee resistance to all diseases and developers should put up strategies to delay emergency of secondary diseases or how to manage them
Milliam Murigi and BBC @millymur1
The past two decades have witnessed the rise of commercial crops that have been genetically modified to boost suitability and production.
Recently, scientists from the University of Edinburgh’s Roslin Institute in UK created pigs that are immune to one of the world’s costliest livestock diseases. This is an indication to show us that gene-edited farm animals are on their way to our farms.
According a recent BBC report, genome, or gene editing (GE) is relatively new and the absence of regulation currently prevents their sale of GE livestock. GE is different to the more widely used technology of genetic modification (GMOs). The former involves the precise alteration of an organism’s DNA, while the latter is characterised by the introduction of foreign genetic sequences into another living thing.
The UK team edited the animals’ DNA to make them resist the deadly respiratory disease known as Porcine Reproductive and Respiratory Syndrome (PRRS). DNA (deoxyribonucleic acid) is a self-replicating material, which is present in nearly all-living organisms as the main constituent of chromosomes. It is the carrier of genetic information.
The production of GE pigs could prevent billions of pounds in losses each year since PRRS causes breathing problems and death in young pigs. Even though in Kenya we don’t have any genetically modified animals at commercial level, there are a number of ongoing trials involving GM vaccines for control of various animal diseases such as Rift Valley Fever, East Coast Fever, African Swine Fever, and Contagious Bovine Pleuropneumonia (CBPP) which are at various stages of research. Also, there are early trials for Trypanosomiasis (sleeping sickness/nagana) resistant cattle.
However, consumers have been reluctant to eat genetically altered animals and crops because of fears of potential risks associated with such products. This concern poses a significant barrier GE pigs farming.
According to Prof Dorington Ogoyi, National Biosafety Authority (NBA) CEO, all GMO products assessed using internationally accepted testing protocols and approved by NBA or equivalent bodies are ascertained as safe and not harmful to human or animal health.
“We are aware that other countries have advanced in animal biotechnologies and some genetically modified animal such as salmon fish and mosquitoes have been released into the environment. Regulatory bodies are established to ensure safety assessments before such products are released to the market,” he said.
BBC reported that researchers deleted a small region of pig DNA but that relatively small edit prevents the PRRS virus from gaining a foothold on the surfaces of pig cells. They then exposed four of their gene-edited pigs to the PRRS virus and none became ill.
Research leader Dr Christine Tait-Burkard said no foreign genes were inserted into the pig. “The tests show that the animals are not weakened or affected in any other way by the process,” she added.
The PRRS-resistant pig project is one of several research efforts across the world to create gene-edited animals for livestock production. Among them is a project to make domestic pigs more resistant to African swine fever.
Researchers are also trying to increase the muscle mass of sheep and cattle by deleting a small section of DNA to mimic a trait that occurs naturally in Belgian Blue cattle.
“The best thing about gene edited animals is that there is easy management of animal diseases through the development of vaccines and diagnostic kits and also increased resistant of diseases and other constraints,” says Prof Ogoyi.
He says introduction of GE animals doesn’t guarantee resistance to all diseases and developers should put up strategies to delay emergency of secondary diseases or how to manage them.
According to Dr Andrew Kiggundu, a Ugandan agricultural scientist, gene-editing technology will dramatically transform livestock breeding in Africa for the better in the next few years. “ It will have a much greater impact on animal production than crops due to the nature of livestock disease in Africa,” he said.
Dr Kiggundu expressed concerns about the complicated regulatory processes that such products must navigate before they are approved and allowed on the market.