IL‐29 can be derived from Th17 cells, and IL‐29 expression was enhanced in lesion skin of psoriasis patients.36 Levels of IL‐29 in psoriatic lesions positively correlated with antiviral protein expression.12 Similarly, serum levels of IL‐29 were elevated in psoriasis patients as compared to healthy controls.37 IL‐29 levels were significantly higher in the skin of AD patients when compared to healthy controls.38 Hashimoto's thyroiditis (HT) is a typical autoimmune thyroid disease. This evidence concerns the gene IFNL1 and psoriasis.