April 23, 2026 – Dialing down an overactive immune sensor can restore tissue health in severe genetic disorders and restore function across multiple biological systems, according to a new study by researchers at the Hebrew University of Jerusalem (HU).  

The human immune system is finely tuned to detect and destroy viral threats, yet it can backfire. When fragments of the body’s own damaged DNA are mistaken for viral invaders, the result is a powerful, misplaced inflammatory response that harms the body it is meant to protect. For decades, scientists believed that the accumulation of unrepaired DNA was the primary cause of cellular decline. This study, published in Genes & Development, challenges that view. 

The research team, led by HU researchers Dr. Marva Bergman, Prof. Itamar Harel, and Prof. Yehuda Tzfati of the Department of Genetics at the Alexander Silberman Institute of Life Science at HU, focused on rare DNA damage-repair (DDR) syndromes such as ataxia-telangiectasia (A-T) and Bloom syndrome. In these conditions, the machinery that normally repairs everyday DNA damage is impaired, leading to widespread genomic instability, neurodegeneration, cancer susceptibility, and premature aging. 

“Our results show that the damage isn’t acting alone,” said Prof. Harel. “It’s the body’s response to that damage, an exaggerated, chronic inflammatory reaction, that drives much of the degeneration.” 

When DNA repair fails, fragments of DNA can leak into the cell’s cytosol, where they activate a molecular sensor known as cGAS. This pathway typically detects viral DNA, but it cannot reliably distinguish between foreign and self-derived fragments. The result is a sustained, sterile inflammatory response that damages tissues. 

The researchers also uncovered a second, unexpected role for cGAS. Beyond triggering inflammation, it can enter the cell nucleus and directly interfere with DNA repair processes. This dual function makes it both a protector under normal conditions and a potent driver of damage when the system is overwhelmed. 

To test whether moderating this response could alter disease progression, the team used a fast-aging vertebrate model that allows rapid evaluation of aging-related processes. When cGAS activity was reduced in this system, key disease features, including neuroinflammation, tissue degeneration, and loss of reproductive capacity, were substantially improved. 

“We weren’t just slowing decline,” said Dr. Bergman. “We saw broad restoration of tissue function. It suggests that the body can cope with more DNA damage than we assumed, if the inflammatory response is kept in check.” 

The implications for treatment are significant. Rather than attempting to repair every DNA lesion, therapies could focus on modulating how the body responds to damage. However, the researchers caution that cGAS also plays a critical role in antiviral defense, meaning that future therapies will need to selectively dampen harmful activity without compromising immunity. 

Beyond rare genetic disorders, the findings may have broader relevance for age-related diseases, where chronic inflammation and genomic instability often coexist. 

Importantly, the researchers note that reversing severe disease processes is different from slowing the intrinsic pace of aging. Still, by identifying how the body’s own alarm systems contribute to decline, this study opens a promising new direction for treating some of the most challenging degenerative conditions.

 The research paper titled “A dual role for cGAS in shaping cellular and organismal responses to genomic instability” is now available in Genes & Development and can be accessed here.

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