GENES RESPONSIBLE FOR SNAPDRAGON FLOWER COLOR IDENTIFIED
Snapdragons are charming tall plants, flowering in a variety of bright colors. However, snapdragon flower colors do not mix, even if they are growing together in a wide area, and this has baffled scientists for a long time.
Researchers from the Institute of Science and Technology Austria (IST Austria and John Innes Center in Norwich compared the genome sequence of 50 snapdragons of each color, and measured how much the sequences diverged between magenta and yellow snapdragon populations. They found “islands” in the genome, which are more divergent between yellow and magenta snapdragons than the rest of the genome. These islands correspond to genes responsible for flower color.
The researchers found two reasons why the snapdragon populations diverge at the flower color genes. Firstly, selection has favored new variants at the color genes, making the flowers more attractive to bees, causing these genes to sweep through the population, and leaving a sharp signal in the DNA sequences. Secondly, the flower genes become barriers to gene exchange. Genes located close to or even between the flower genes cannot easily be swapped between the populations, and so the region of genome around the genes that determine flower color become divergent.
For more details, read the news details from IST Austria.