But Axona, which as been on the market since 2009, might keep healthy brain cells alive longer, says Chief Executive Holger Kunze.

WSJ: 'Medical Foods' and Supplements for Brain Health Advance

The price of silicon, the chief component of photovoltaic cells, is already falling.

ECONOMIST: Clean technology in the downturn

"The fifth base is like a switch - switching on the genes and making cells healthy or diseased, " Alex Olek, the chief executive of Epigenomics, told the BBC.

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