Noncoding gene sequences control gene expression and influence disease processes
Stretches of regulatory DNA once thought functionless may orchestrate networks of genes. [© Mopic - Fotolia.com]
In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells’ shape and function.
Their report adds to growing experimental support for the idea that all that extra stuff in the human genes, once referred to as “junk DNA,” is more than functionless, space-filling material that happens to make up nearly 98% of the genome. The paper adds to a growing body of knowledge establishing a considerable role for this material in the regulation of gene expression and its potential role in human disease...
Over the past few years, as high-powered analytical tools and genomic information have become available, the function of introns, such as transcription factor recognition sequences, has become better understood. And, as John Stamatoyannopoulos, M.D., associate professor of genome sciences and medicine at the University of Washington, points out, while only about 2% of the human genome codes for proteins, “Hidden in the remaining 98 percent are instructions that basically tell the genes how to switch on and off." His laboratory focuses on disease-associated variants in regulatory regions of DNA.
The footnote to all of this is probably that knowing individual gene sequences that encode specific proteins is only the beginning of understanding the complexity of the human genome, but it may show how introns and other mechanisms control gene expression and ultimately shed light on many human diseases.
