Science - September 22, 2010

Applying the zinc finger technique

Wageningen UR Plant Breeding is testing new gene technology from Dow AgroSciences for potato research. Known as zinc finger technique, it makes it possible to adapt selected pieces of DNA.

Dow AgroSciences, a daughter company of Dow Chemicals, owns all the rights to a patented method of adding, changing or switching off genes in plants in a precisely targeted manner. Zinc fingers are synthetic proteins which can bind to DNA and influence gene expression. This zinc finger technique can recognize and adapt a specific DNA sequence.

Potatoes
The Plant Breeding chair group wants to use this technique to improve the breeding of high-starch potatoes. 'We have a lot of knowledge about the genetics of starch composition in potatoes', says researcher Frans Krens. 'One of the things we want to see is whether this technique can dictate the DNA sequence in all four chromosomes in the potato at once, so that we can transfer the useful characteristics of all the reproductive cells to new generations.' Targeted transfer of genetic characteristics to the next generation is very tricky in potatoes because the crop is tetraploid: its seedlings get two chromosomes from Dad and two from Mum.

Licenses
Dow's technique is called EXZACT TM Precision Technology. Dow AgroSciences has plans to market a high-starch potato itself, says Krens. 'Dow wants to have its technique used in several labs, to test its usefulness.' PRI will use the technique for potato research. In January the Wageningen biotechnology company Keygene made a similar deal with Dow in relation to tomato research. If this testing phase shows that the technique works well for several crops, breeders will soon be able to obtain licenses from Dow to allow them to use the zinc finger technique. Meanwhile, Krens is delighted with the current agreement. 'We like to have the latest breeding techniques at our disposal.'