Therefore, we propose that hematopoietic stem cell transplant recipients carrying homozygous rs1021737 are more prone to develop IPA because of the reduced CTH enzymatic activity and thus persulfidation level of many proteins relevant for the antifungal response of lung resident cells, which leads to a dysregulation of the initial antifungal response, including reduced antifungal potency and an imbalanced cytokine production. The gene discussed is CTH; the disease is Ito hypomelanosis.