Among 1873 eligible SSc patients, the presence of DU was significantly associated with gastrointestinal involvement (OR 1.88, 2.04 and 1.74; p < 0.001) and serum ATA positivity (OR 2.15; p < 0.001), as well as with telangiectasias, sclerodactyly, digital pitting scar, and calcinosis (OR 1.40, p = 0.005; OR 3.43, p < 0.001, OR 9.12, p < 0.001 and OR 2.77, p < 0.001; respectively). The gene discussed is ATM; the disease is telangiectasis.