¿Qué hay en el ADN no codifi cante?

Abstract

More than 95% of our DNA is non-coding. This does not mean that 98% of the genome has no role at all, on the contrary. But, what is it there for? Part of this DNA contains cis-regulatory sequences that control when, where and how much a gene is transcribed. Cis-regulatory sequences can activate (enhancers) or suppress (silencers) transcription. These enhancers or silencers can be very far from the promoter they act on, or even in introns of adjacent genes. Some of them can control several neighboring genes at the same time. These sequences are therefore called Locus Control Regions. In addition, certain cis-regulatory sequences can also prevent the action of enhancers or silencers on promoters when they lie in between. These types of sequences are called insulators, and play essential roles in generating different regulatory landscapes for neighboring genes. Despite their essential function in gene regulation, and in contrast to coding sequences, their language is mostly unknown. This prevents their identifi cation in the genome just based on their DNA sequences. Therefore, the goal for the next decade is to unravel this language and identify all cis-regulatory elements in the human genome and their implication in human diseases associated with mutations in non-coding DNA.