A group of international scientists from International Institute of Tropical Agriculture (IITA), in Nigeria, the Japan International Research Centre for Agricultural Science (JIRCAS), the Iwate Biotechnology Research Centre (IBRC), Japan, and the Earlham Institute and The Sainsbury Laboratory of the United Kingdom, has finally revealed the full genome sequence of one of Africa’s poorly understood but vitally important crop – the white Guinea yam (Dioscorea rotundata Poir.).
This breakthrough which was titled “Genome sequencing of the staple food crop white Guinea yam enables the development of a molecular marker for sex determination”, and published in BMC Biology (an open access journal) is a big development in science and food security in West Africa as yam is central to the culture of many societies in this region.
The White Guinea yam, popularly called “white yam”, by locals is a species of yam native to Africa. It is one of the most important cultivated yams in West Africa, including countries such as Ivory Coast, Ghana and Nigeria.
Yam is Nigeria’s most important cash crop worth nearly $14 billion annually; one-third of Nigerians, nearly 60 million people depend on yams as a main source of income; yam is Nigeria’s no. 1 source of dietary calories; and the governments is currently promoting yam exportation for foreign exchange.
On June 29, 2017, a total of 72 metric tons of yam will leave the shores of Nigeria to Europe/US, heralding a new dawn in our food exports.
— Audu Ogbeh (@AuduOgbeh) June 26, 2017
Despite all the importance of yam, relatively little is known about its genes or DNA, when compared with other staple crops such as wheat and rice. This means unlike wheat and rice crops, yam crop has not been improved genetically.
Also this development is not only big. It is timely too, as yam production is currently declining and the demand for yam is currently overwhelming—much more than supply.
So what is genome sequencing and how do we gain from Yam genome sequencing?
A genome is an organism’s complete set of DNA, including all of its genes. Each genome contains all of the information needed to build and maintain that organism. So with Genome sequencing scientists can figuring out the order of DNA nucleotides, or bases, in a genome—the order of As, Cs, Gs, and Ts that make up an organism’s DNA. The human genome is made up of over 3 billion of these genetic letters.
So with this knowledge of the genome sequence of yam, scientists will be able to improve the crop’s nutrient and yield.
“This is an important breakthrough. It means that yam has joined those crops with a full genome sequence, such as rice and other better-known crops,”
“The implications are profound. Knowing the full DNA sequence will greatly facilitate our understanding of how genetics controls key traits such as flowering, diseases, and others including quality traits, and this in turn will make the breeding of new varieties faster and more precise,” he further explains.
“The genome resource will help to overcome the many challenges facing yam farmers in Africa and other parts of the world,” added Professor Ryohei Terauchi, Kyoto University and Iwate Biotechnology Research Institute, study leader and corresponding author.
This sequencing also allows yam scientists distinguish between male and female plants at the seedling stage there by saving them months of work time.