Indeed, a mass spectrometry experiment (SILAC) on SIFD patient and control cells identified changes in the abundance of distinct groups of proteins, and we have validated decreased expression of Calponin 2 in SIFD patient-derived cells and cells with acute reduction of TRNT1. This evidence concerns the gene CNN2 and congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome.