Worms, sponges, snails, flies and men have the gene to grow and for everyone it is the same. The gene is very small, has only 21 nucleotides, but plays an important role when these organisms are in the early stages of development. The Let-7 gene has been found in very primitive beings and is believed to have had great importance in biological evolution.
The discovery, in addition to being a scientific value, has a great practical value, since the presence of the gene in the lower organisms allows to learn how it is activated and deactivated. The Let-7 gene can be used to resolve alterations that occur in human growth and development.