Humans adapt through language and culture, passing down knowledge from one generation to the next. Corn plants can鈥檛 talk, so they solve the problem of adaptability in a different way: they use 鈥渏umping genes鈥 to shuffle the genetic deck over generations. Jumping genes鈥攏ow called transposons鈥攚ere discovered by Nobel Prize-winning 黑料吃瓜资源 (CSHL) geneticist Barbara McClintock in the 1940s. Decades later, CSHL scientists are still expanding on her work. Doreen Ware, a CSHL adjunct professor and research scientist at the US Department of Agriculture (USDA) and her colleagues, published genome sequences from 26 different strains of corn in the journal Science. The genomes describe a large portion of the genetic diversity found in modern corn plants, including transposons and genes that regulate desired crop traits.
Corn has been bred to grow in various climates of the world, from temperate to tropical, and from highlands to lowlands. Ware says:
鈥淗umans have brains. Our main adaptive component is our ability to transfer culture and knowledge, right? And that鈥檚 how we deal with our environment. A plant鈥檚 strategy is to have a fluid genome. They have a very intimate relationship with these transposons, where they use them to bring in new genetic diversity so that they can deal with these events because they can鈥檛 run away. They鈥檙e not going to go into the house, and they鈥檙e not going to move water to them.鈥
Ware and her colleagues, including CSHL Professor & HHMI Investigator Rob Martienssen and CSHL Professor W. Richard McCombie, mapped the first corn genome in 2009; they have been filling in gaps ever since. Like a continental landscape, genomic maps have areas that are full of features (like well-mapped cities), whereas others are more like deserts (vast and uncharted). With recent techniques, the team of scientists charted difficult stretches of the genome, even the deserts. These complete genomes allow researchers to locate and study both important crop genes and the nearby regions that regulate their use. Ware notes, 鈥渨e had little access to the regulatory architecture of corn before.鈥
The new collection reveals how the corn genome was shuffled over time. Ware says:
鈥淭hese genomes provide us a footprint of that life history. Different strains have experienced different environments. For example, some came from tropical environments, others experienced particular diseases, and all those selective pressures leave a footprint of that history.鈥

Corn is one of the most common agricultural staples in the world, with more than grown in the US from 2018 to 2019. Equipped with more detailed maps of the corn genome, scientists have a head start in developing crops for a rapidly changing climate. Ware explains, 鈥淭he Midwest is not going to have the same temperature profile twenty years from now. The genomes provide broader insights into corn genetics, and this, in turn, can be used to start optimizing corn to grow in future environments.鈥
The project was a multi-institutional effort with researchers at CSHL, USDA, University of Georgia, Iowa State University, University of Minnesota, and Corteva Agriscience. The new collection of genomes is available online at .
Written by: Luis Sandoval, Communications Specialist | [email protected] | 516-367-6826
Funding
US Department of Agriculture, the National Science Foundation, US Department of Agriculture Hatch Project, National Science Foundation Postdoctoral Fellowship in Biology, National Science Foundation Graduate Research Fellowship, National Science Foundation Research Traineeship, US Department of Agriculture Agricultural Research Service, US Department of Agriculture Agricultural Research Service Project, and National Science Foundation Integrative Organismal Systems
Citation
Hufford, M.B., et al., 鈥淒e novo assembly, annotation, and comparative analysis of 26 diverse maize genomes鈥, Science, August 6, 2021. DOI:
Principal Investigator

Doreen Ware
Adjunct Professor
Ph.D., Ohio State University, 2000
