Major disease resistance trait found in soybean
Apparently, it's the sheer number of the triple-genes that makes soybeans resistant, Bent says. "We have evidence that what confers the resistance is higher expression of all three genes," not a mutation in the genes. "The fact that the genes are making more of their product is what makes for resistance."
Identifying the genes needed for resistance should help plant breeders quickly identify resistant plants, speeding the quest to breed soybeans with stronger nematode resistance. Biotechnologists can also now work with these genes to achieve better nematode resistance.
More broadly, Bent notes that multiple gene copies are being found more commonly, so finding repeats of a string of genes with a single function "may not be a one-shot thing. Is this the tip of the iceberg? Is there a lot more of this going on than we know?"
As gene sequencing gets cheaper and faster, "people are discovering that these copy number variations are much more common than we suspected, especially in plants," Bent says. "Now, we have given a concrete example of a useful trait, that is explainable due to the copy number variation of a string containing several active genes."