Stylized stock image of genome sequencing.
Transposable elements, sometimes called “jumping genes,” are DNA sequences that can move from one location to another. They’re estimated to make up nearly half of the human genome and are mostly inactive. Because so little of the human genome is dedicated to encoding proteins (i.e., exons), scientists propose that any potential adverse effects of transposable elements are likely on gene expression, which are controlled by various regulatory elements in the genome, such as enhancers.
In a recent study from the Levin Lab, researchers looked for transposable elements that may potentially increase the risk of psychiatric disorders, which have a substantial genetic component as demonstrated by studies of twins. In addition, genome-wide association studies (GWAS) in schizophrenia and other disorders have identified over a hundred genetic areas that each make small but measurable contributions to disease risk. There is also overlap of these genetic areas among different psychiatric disorders, suggesting shared regulatory pathways in neurons.
The study team evaluated over 17,000 transposable elements and identified 76 that may have a role based on GWAS. From this list, they conducted further analyses to identify 10 transposable element insertions that are likely linked to neurologic and psychiatric conditions. As proof of principal, they tested the lead candidates and observed regulatory effects on gene expression in human neural stem cells. By identifying transposable elements that are linked to risk of neurologic and psychiatric diseases, the team provides a valuable list of causal candidates that merit additional research.
Learn more about the Cell Regulation and Development Group: https://www.nichd.nih.gov/about/org/dir/affinity-groups/CRD.