To examine the effect of TRNT1 mutations on the cellular response to oxidative stress, two control, and four SIFD patient-derived fibroblasts were treated with hydrogen peroxide (H2O2) or sodium arsenite (NaAsO2) to induce oxidative stress. The gene discussed is TRNT1; the disease is congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome.