Publishing in the Nov. 19 issue of Science, the researchers, whose senior and first author are at Cornell, have identified the first map of haplotypes – sets of closely linked gene variants known as alleles – in the maize genome. They have identified and mapped several million allele variants among 27 diverse inbred maize lines. The lines selected for study included a cross-section of maize types commonly used for breeding while also representing worldwide maize diversity.
The haplotype map “will help develop molecular markers and tools that breeders and geneticists around the world can use to study maize and improve maize varieties,” said Ed Buckler, the paper’s senior author, a USDA-ARS research geneticist in Cornell’s Institute for Genomic Diversity and an adjunct professor of plant breeding and genetics. Michael Gore, a graduate student in Buckler’s lab, is the paper’s lead author.
The other co-authors are affiliated with the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS), Cold Spring Harbor Laboratory and University of California-Davis.
In the last century, maize breeders have found limitations in recombination (the ability to shuffle genetic variation), where large regions genetic material fail to recombine near the chromosome’s center, called the centromere. To overcome this, breeders have crossed two complementary lines, resulting in a new line with higher yields and vigor.
However, because large regions of the maize chromosome are less accessible, breeders cannot arrive at optimal genetic combinations. The study has revealed a great deal of genetic variation near the chromosomes’ centromeres, which resist recombining. Now, breeders can use molecular markers to identify desirable genetic variants and new genetic technologies to move the desired variation onto the same chromosomes and create new, more productive lines with desired traits.
The study revealed more than 100 large regions (selective sweeps) on the genome where breeders selected for a gene during domestication. In doing so, genetic diversity was lost around those genes.
The study also identified regions of genes shared by all maize species as well as regions that are different based on the geographic adaptations of lines of plants. For example, the study identified almost 200 highly differentiated regions that result from adaptations in tropical and temperate maize.
“This survey of genetic diversity provides a foundation for uniting breeding efforts across the world and for dissecting complex traits through genomewide association studies,” said Buckler.
The first complete sequence of the maize genome appears in the same issue of Science.
The haplotype study was funded by the National Science Foundation and the USDA-ARS.
Blaine Friedlander | Newswise Science News
New research recovers nutrients from seafood process water
31.10.2018 | Chalmers University of Technology
Plant Hormone Makes Space Farming a Possibility
17.10.2018 | Universität Zürich
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
16.11.2018 | Health and Medicine
16.11.2018 | Life Sciences
16.11.2018 | Life Sciences