EXTL3 dysfunction identified as a driver of aberrant bone development in severe familial ankylosing spondylitis.
Hilliquin S · 2026 · Annals of the rheumatic diseases
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What this paper found
In a family with unusually severe ankylosing spondylitis, a rare change in a gene called EXTL3 was found, and mice carrying it developed early joint bridging and abnormal bone through a pathway involving heparan sulfate and Wnt signalling. It identifies a bone-formation mechanism separate from inflammation, which may explain why some people fuse despite well-controlled disease.
Why this is on the map
Rare-variant genetics pointing at the fusion process itself rather than immune activation; a new angle for the genomics thread.
On the map under this thread
DOI: 10.1016/j.ard.2026.06.031 · opens in a new tab. The full paper is on the publisher’s site, not here.
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