Significant elevations in the circulating concentrations of the vascular endothelial growth factor (VEGF), a key mediator of angiogenesis, have been observed in several types of RDs, e.g. rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, psoriatic arthritis, systemic lupus erythematosus, systemic sclerosis, and Sjögren’s syndrome [13–19]. This evidence concerns the gene VEGFA and ankylosing spondylitis.