For the 3 SCID-patients and the Nijmegen breakage syndrome case with SCID-like phenotype identified by screening in the national program the TRECs results were ready at day 4, 13, 4, and 6, respectively, and their molecular diagnosis (DCLRE1C, JAK3, IL2RG, NBN) were molecularly confirmed on day 8, 15, 6, and 8 after birth, respectively, using the initial blood spot. The gene discussed is IL2RG; the disease is Nijmegen breakage syndrome.