The failure of the EC's regulatory committee to reach a qualified majority on the approval of the BASF GM innovation means that the dossier will be passed on to the Council of Ministers, who will decide on the approval within the next three months.
In the event that the vote in the Council of Ministers does not result in a qualified majority either, the European Commission will decide on the dossier.
The approval is a prerequisite for commercial cultivation of Amflora. If approved, BASF's starch potato will be the first genetically enhanced product to be permitted for cultivation in Europe since 1998.
But environmentalists have argued that the cultivation of GM potatoes would increase the risk of contamination of the food chain.
Europe is already a significant producer of potato starch. Normal potato starch is valued for its high molecular weight (giving excellent thickening properties) and low levels of fat and protein compared to wheat and cornstarch.
Nearly all starches have two components - a high molecular weight, highly branched molecule with excellent thickening properties, called amylopectin, and a smaller, linear molecule which gels, called amylose.
The 20 per cent amylose in normal potato starch limits its usefulness for many industrial applications. Separation of the two components is not economic, so most industrial starch is first chemically modified to reduce the gelling tendency.
Amflora is a genetically optimised potato that produces pure amylopectin starch. BASF said that this breakthrough was achieved by tweaking the pathway by which it is made in the plant cells.
Both amylopectin and amylose are built from the same simple sugar dextrose and the different physical properties come about because of the way the monomers are joined.
The linear chains of amylose are constructed using a single enzyme called GBSS (Granule Bound Starch Synthase). Scientists have used biotechnology to make a back-to-front copy of the gene (called an anti-sense gene) and then inserted this into the DNA of a conventional potato using a bacterium (Agrobacterium tumefaciens). The anti-sense gene interferes with the operation of the normal gene, and no GBSS is produced. In the absence of this enzyme, the polymerisation of dextrose all goes in one direction, to produce amylopectin.
The EC published the result of the vote on Amflora earlier this week. 134 votes supported an approval, 109 opposed it while 78 abstained. The qualified majority of 72.3 per cent, needed for immediate approval, was not reached.