Scientists have moved a step closer to learning the genetic secrets of maize, one of the world's most important food crops, and using this knowledge to boost crop yields.
The researchers, led by Joachim Messing, director of the Waksman Institute of Microbiology at Rutgers University in New Jersey, United States, have published a series of papers providing the most comprehensive picture yet of the crop’s evolution and genetic structure.
"This research will help enable scientists and farmers to make major improvements in one of the world's most significant crops," says Messing.
"More nutritious maize is critical for Africa," he says, adding that it should be possible to boost the crop's nutritional value because "it already has all the genes necessary".
According to Messing, the richness of the maize genome means that increasing its nutritive value would not require adding genes from other species, but only changing the way existing genes function.
"One example is amino acids, which are stored as proteins in the seeds that we eat," says Messing. Some maize varieties have more nutritious proteins, but the genes controlling their production can be 'silenced' when the variety is crossed with other strains. Messing anticipates being able to prevent this silencing by moving a short sequence of genetic material called a 'regulator' from a gene that is not silenced to the one that is.
The research also revealed that the maize genome is highly complex because many of its genes have moved to different locations on chromosomes during its evolution. This phenomenon – unknown in any other species – has implications for genetic engineering.
According to Messing, it means that fears that genetic modification could lead to instability in a species’ genetic material are unfounded.
Messing's team's findings are presented in three papers in the journal Genome Research and one in the Proceedings of the National Academy of Sciences.
Genome Research 14, 1916 (2004)
Genome Research 14, 1924 (2004)
Genome Research 14, 1932 (2004)
PNAS Early Edition Article #04-06163, Sept. 20, 2004