Can changes in noncoding DNA affect health and development?
While noncoding DNA does not contain genes, variants in these regions can disrupt gene regulation and protein production, leading to various health conditions.
The Role of Noncoding DNA
Scientists have determined that changes in regions of DNA that do not contain genes—known as noncoding DNA—can lead to disease. Many of these regions control gene activity, determining when and where genes are turned on or off, or are involved in protein assembly.
A variant in noncoding DNA can disrupt these processes by:
- Turning on a gene in the wrong place or at the wrong time.
- Reducing or eliminating the production of an important protein.
Regulatory Elements and Disease
Variants in noncoding DNA can disrupt several types of regulatory elements:
- Enhancers: Attach proteins that help turn on particular genes. Alterations here are linked to conditions like isolated Pierre Robin sequence, which involves the SOX9 gene.
- Promoters: Where proteins that turn on genes attach.
- Insulators: Where proteins that help shape gene activity attach.
- Silencers: Where proteins that turn off genes attach.
Additionally, some noncoding DNA provides instructions for RNA molecules (such as transfer RNAs, microRNAs, or long noncoding RNAs) that regulate gene activity or assemble proteins. Interrupting these molecules has also been implicated in disease.
Types of Genetic Changes
The same types of genetic changes that affect genes—such as substitution variants, insertions, deletions, duplications, and translocations—can affect health when they occur in noncoding DNA. These variants can be inherited or acquired during a person’s life. Because much is still unknown about the function of noncoding regions, linking these genetic changes to specific health conditions remains a growing and complex area of research.