From the Nucleus to DNA Looping (IMAGE) Babraham Institute Caption Image shows a cut-away cell nucleus (top left) with one chromosome highlighted and enlarged on the right. Each chromosome contains hundreds of genes. Enlarged section of the chromosome (bottom left) shows how chromosome folds to allow distal control regions of the DNA thread (yellow) to directly interact with a gene (blue). These distal control regions switch genes on and off. Small changes in the DNA sequence of the control regions may interfere with normal gene expression and lead to disease susceptibility. Credit Image: Drs C. Varnai and P. Fraser, © The Babraham Institute 2016. Usage Restrictions Used with credit to The Babraham Institute License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.