Genetic study reveals four distinct profiles of giant cell arteritis

Researchers have identified the first genetic markers linked to different clinical forms of giant cell arteritis, offering a clearer view of why the vascular disease varies so widely between patients.

The international team analysed genetic data from nearly 3,500 patients and more than 15,500 people without the disease across 10 countries in Europe and North America. It found 14 regions of the genome associated with particular manifestations, including seven within the HLA region, which plays an important role in immune responses.

Giant cell arteritis is the most common form of vasculitis in people over 50. It inflames medium and large arteries and can weaken or obstruct blood flow, sometimes causing permanent sight loss, stroke or aneurysms.

Using a statistical model, the researchers classified patients into four genetic profiles: predominantly cranial disease, a mixed pattern, mainly extracranial disease, and a group with a high predisposition to severe complications caused by restricted blood flow, including irreversible vision loss.

The findings suggest that genetics influences not only whether someone develops the condition but also how it appears. The profiles could eventually help clinicians identify high-risk patients earlier and tailor monitoring or treatment. However, the researchers say prospective studies following patients over time are still needed to validate the results before genetic information can enter routine clinical practice.