Tomato leads genome project
ingredient used widely in the food industry as scientists set to
sequence a portion of the gene-rich regions of 12 tomato
chromosomes.
The move is part of an international effort to develop a reference genome sequence for the plant family Solanaceae, to which the tomato belongs along with aubergines, paprika and the potato.
Scientists at Cornell University, the Boyce Thompson Institute and Colorado State University will sequence 400,000 bacterial artificial chromosomes (BAC) reads end assembled from the tomato (Solanum lycopersicon) genome.
"The understanding of the tomato genome is essential to the continued use and cultivation of this agriculturally significant family," said Fei Lu, CEO of SeqWright, a contract research organisation responsible for collecting by the Solanaceae Genomics Project (SOL) consortium.
Tomatoes are known to contain the health-boosting antioxidant lycopene, a carotenoid that has attracted significant attention in recent years as it has been linked in some research to reduced risk for cancers, especially prostate cancer. New findings also suggest that it could have a protective effect on heart disease, the cause of more deaths among women than any other disease.
The lycopene market is expanding significantly, with growth rates forecast at over 100 per cent in a recent report on the carotenoids market from Frost & Sullivan. The report values the ingredient at $34 million (€27.6m) in 2003, and with growing demand, new sources of the nutrient will attempt to lift this figure further.
"BAC end sequencing is one of the foundation efforts that will support all participants in the international effort to develop a reference genome sequence for the plant family Solanaceae," said Dr Jim Giovannoni at the Boyce Thompson Institute.
Earlier this year scientists at the John Innes Centre (JIC) in the UK and Institute of Food Research (IFR) in Norwich, UK identified the gene - HQT - as the producer of the powerhouse antioxidant chlorogenic acid (CGA) that protects the tomato against stress and disease.
They found that by increasing the activity of HQT, CGA levels in the tomato fruits were lifted, helping to protect them against attack from bacterial disease. CGA could also protect humans eating the tomatoes against degenerative, age-related diseases, the scientists purport.
"CGA is the main polyphenol in this category in tomatoes. Now we have identified the gene for the enzyme that produces it, we can look for genes that produce similar compounds in other plants, with benefits for agriculture and for human nutrition," said Dr Tony Michael, project leader at IFR.
Knocked by over production in 1999-2000, the global tomato processing industry has seen prices tumble in recent years, a situation that is only now just starting to improve. But growing competition from China - now the third largest producer although 10 years ago a small player, has also diluted prices.
AMITOM, the Mediterranean International Association of the Tomato Processing recently told FoodNavigator.com that prices in the US and Europe were coming in at $50 to $60 a ton, compared to about $30 a ton from China. California is currently the largest tomato processor, followed by Italy and the new kid on the top block, China.
In Europe, 8.5 million tons of tomatoes are cultivated annually with 1.5 million tons sold directly to the consumer and 7 million are processed for products such as ketchup and sauces.
