Four-leaf clovers are very well known. According to popular legend, each leaf represents, in order, hope, faith, love and luck.
For Wayne Parro's team, from the University of Georgia, in the USA, it is the presence of two versions of the same gene that determines the number of leaves of the white clover, Trifolium repens . One, the dominant, inhibits the formation of the fourth leaf, and the other, triggers its growth.
In order for it to develop four leaflets, the clover has to inherit two versions of the recessive gene. Hence, finding a specimen of this type is something so rare.
