IL23R polymorphisms (rs11209026, rs11465804) were associated with susceptibility to ATA-positive SSc (P = 0.001, P = 0.0026, respectively) and considered protective against the development of PAH in patients with SSc (P = 3 × 10−5, P = 1 × 10−5, respectively). Here, IL23R is linked to systemic sclerosis.