Furthermore, analysis of a GEO dataset (GSE186063) revealed that SPRY1 gene expression was significantly downregulated in the PsA lesional skin compared with psoriasis lesional skin and ankylosing spondylitis normal skin, which suggests that SPRY1 downregulation in the skin is more strongly associated with PsA than with psoriasis. This evidence concerns the gene SPRY1 and ankylosing spondylitis.