Useful “Junk DNA”
Even DNA that is not conserved in evolution could promote the expression of genes...
What is important in the enormous information book that we call the genome? We know very little about this and the current view is that the part of the genome that codes for proteins is essential. In addition, the portion of DNA that is conserved during evolution is likely to be also functionally important.
Three research groups homed at the EPFL and at the University of Geneva, those of Denis Duboule, Didier Trono and Stylianos Antonarakis, led a collaborative study to explore the question of which part of the genome is functional, in an unbiased way. Marc Friedli, working in all three laboratories, took a region of DNA from the mouse genome, cut it in small pieces and tested each fragment for the ability to control the expression of genes in the developing mouse embryo. The results revealed that, amazingly, even DNA that is not conserved in evolution and was considered previously as “junk DNA” could promote the expression of genes. This function was hitherto only known to occur in conserved DNA.
The methodology described could be used for the study of the entire genome. This collaborative study is published in the December 2010 edition of PLoS ONE. The conclusion of this research is that many regions of the previously considered “junk DNA” could be responsible for a fraction of the myriad of human disorders and genetic traits.