by Monica Heger
Researchers report in Science that they have sequenced the genome of a common variety of maize, which could lead to improved crops and help piece together the evolution of the plant. “When you have the genome sequence, you have an important part of the instruction manual,” says Richard Wilson, geneticist at Washington University’s Genome Center in St. Louis, who led the research.
Maize's genome, which is made up of some 32,000 genes, has been made available online, so scientists, farmers, seed companies or anyone else can study the genes and attempt to breed the plants with the most desirable traits. “It’s going to be really important for the agricultural business,” says Wilson.
Maize crops could be bred for genes that would make them favorable for specific locations and needs. For instance, some varieties of maize have a high starch yield, which is important for feeding people. But, those varieties don’t necessarily grow well in extreme climates, says Wilson. Using breeding techniques and the new data, you could try to combine maize with genes that enable it to grow in a hot, dry climate with maize that has the high starch yield genes. The new type of maize would be beneficial in places such as Texas or even in sub-Saharan Africa.
Using breeding to select for desirable traits is more efficient than genetic engineering, which occurs when scientists attempt to insert a specific gene into a crop to get a specific trait. Genetic engineering is “a little artificial,” says Wilson. “Nature is always going to do it better. If we can give nature a little assistance, that’s really the key.”Knowing the genome will also help in tracing maize’s evolutionary history. “It’s like DNA forensics that you might see on CSI,” says Wilson. “When you know the genome sequence, you can start to piece together its family tree.”
In particular, it now appears that hundreds and maybe thousands of genes were involved in the domestication of maize, says Ed Buckler USDA-ARS researcher at Cornell University, who worked on the research. “It wasn’t just one or two genes that did everything.”
The results mark the culmination of a 4-year, $29.5 million project that was a collaboration between scientists from many different universities. The next step will be to figure out how maize’s 32,000 genes interact, and which ones are linked to desirable traits.
USA Today
