Study links lifelong dna mutations to autoimmune thyroid diseases

Wednesday 15 April 2026 - 07:50

By: Dakir Madiha

Study links lifelong dna mutations to autoimmune thyroid diseases

A study published in Nature reports that dna mutations acquired over a person’s lifetime may disrupt the immune system’s natural controls and contribute to autoimmune thyroid diseases. The research, led by scientists from the Wellcome Sanger Institute, Cambridge University Hospitals, and the University of Cambridge, provides strong evidence for a theory first proposed in the 1950s. The findings suggest new treatment paths that target faulty immune cells without suppressing the entire immune system.

Researchers used NanoSeq, a high-precision dna sequencing method, to examine thyroid tissue samples from patients with autoimmune conditions. They found that b cells, a type of white blood cell central to immune defense, had independently accumulated damaging mutations in key immune checkpoint genes. These included TNFRSF14 and CD274, also known as PD-L1. In several cases, individual cell clones carried multiple driver mutations that had developed over years before symptoms appeared, a pattern previously associated mainly with cancer development.

These mutations removed critical safeguards that normally prevent the immune system from attacking healthy tissue. Scientists noted that similar gene disruptions are already known to trigger thyroid autoimmunity in cancer patients receiving immunotherapy. The new study demonstrates that such mutations can also arise naturally in patients with autoimmune diseases, offering a direct biological explanation for the condition.

The findings mark a shift in understanding autoimmune disease mechanisms. Researchers say somatic mutations in immune cells may play a central role, a concept that remained untested for decades due to technical limits. Independent experts described the work as a major advance that clarifies long-standing questions about how these diseases develop and persist.

Autoimmune diseases affect an estimated 5 to 10 percent of the global population, yet current treatments rely on broad immune suppression. The study found that mutations are spread across many small groups of b cells rather than a single dominant clone. This suggests future therapies will need to target a diverse set of abnormal cells. Early observations indicate similar mutation patterns may exist in other autoimmune conditions, pointing toward wider clinical implications.