Gene map of Tomato (Solanum lycopersicum) (2n = 24)

    Garden tomatoes have a long history of cultivation, and the genetics of various ornamental varieties is well understood. Small differences among varieties can have enormous commercial consequences. For example, wild varieties tend to have small, dense fruits. Crossing of one such wild strain to the common commercial strain resulted in a plant with in an increase in solid matter of several percent. Where each 1% of solid material in plants used for catsup or tomato paste is worth several million dollars annually, there is strong economic incentive to understand tomato genetics. The complete genome sequence of the cultivar Heinz 1706 was published in 2012.

    The first genetically modified organism used as human food was the Flavr Savr tomato, first marketed by Calgene in 1994. Calgene inserted a genetically engineered anstisense gene that interfered with transcription of the mRNA for an enzyme responsible for early ripening and softening of tomato fruit. This was intended to ease handling and increase shelf life, however the Flavr Savr strain was not considered to have as good a taste as typical tomatoes, and still softened earlier than desired. In combination with the added cost of production, Flavr Savr was off the market by 1997.

Figure ©2002 by Griffiths et al.; all text material ©2014 by Steven M. Carr