Yet, the case definition in this former study was based primarily on clinical findings and also included some patients with syndromes (i.e., 22q11.2) and diseases, which may clinically present as SCID, but are usually not detected by TREC-NBS (e.g., ORAI1 deficiency [28]). Here, ORAI1 is linked to hyperinsulinemic hypoglycemia, familial, 4.