A 'real heirloom tomato' represents a plant that has been extensively modified by humans through the slower genetic modification process of artificial selection.
The wild ancestor of the tomato is the size of a pea.[0]
I'm aware of FlavrSavr as my line of work is plant genome engineering. My response was to a comment which was presumably directed toward the article that was posted. In that article, the new tomato variety is not engineered in a way to affect shelf-life. Besides, per acre, almost all of our GM crops are engineered for producers' benefit. Out of the many registered GM varieties, only a small handful are associated with something other than pesticide resistance, Bt, or environmental resiliency.
The wild ancestor of the tomato is the size of a pea.[0]
[0]https://en.wikipedia.org/wiki/Solanum_pimpinellifolium