Lactuca sativa, or garden lettuce, is the most valuable
fresh vegetables in the United States, bringing in $2.4 billion a year. Scientists
and lettuce farmers are so interested in mapping the genome of the Composiate
family because of its evolutionary success. There are many different types of
lettuce and they grow in multiple environments which makes them the most successful
family of flowering plants. Being able to see why they are so successful could
help farmers genetically modify other crops in order to make them just as
successful. During the mapping, scientists found that 45 million years ago the
genome of lettuce was “triplicated”. This means there are three copies of each
gene all showing up in different spots of DNA. It is believed that this triplication
is what has given the Compositae family so much success.
