So this week, in over 30 different journals, a detailed study was reported on the nature of the over 3 billion nucleotides (the fundamental building blocks of genes and thus of DNA) that make up the human genome. In the turn of this century, the human genome was completely sequenced (identified at the nucleotide level). At that time it was thought that only 1.5% of those 3 billion plus nucleotides were functional and directly coded for proteins. Much of the remaining 98.5% of the human DNA material in all of our chromosomes where thought to be junk DNA, thus serving little to no function.
However, this has been challenged greatly by new studies published this week suggested that as much as 80% of all the DNA in our cells are functional. They define functional as the following: nucleotides that do not code for proteins but that does for RNA that is not translated in proteins (but can be regulatory in nature), nucleotides that themselves bind proteins, or nucleotides that affect the shape of the DNA in one way or another. Thus is a far cry from the thought that most of the genome in our bodies is junk.
What does this mean in the real world and will it revolutionize medicine and science. It certainly means that labs all around the world working on their favorite gene or gene location will pay a lot more attention to sequences outside of the traditional gene unit (usually includes, enhancer, promoters and the introns and exons of the genes themselves). More and more data will probably come out from labs on novel regulatory mechanisms from far away gene sequences and so on. However, clinically t is doubtful that this new finding will bear any direct relevance to treatment and disease. Just as the impact of the human genome was rather weak after the initial wave of euphoria, this too will pass.
- Opinion: What Is the Human Genome? (the-scientist.com)
- Most of what you read was wrong: how press releases rewrote scientific history (arstechnica.com)
- The ENCODE Project (ribosometranslation.wordpress.com)
- ENCODE Media FAIL (or, Where’s the Null Hypothesis?) (thefinchandpea.com)