NFKB1 and common variable immunodeficiency: Overall, based on the clinical symptoms observed at the time of this study across 6 pedigrees, the penetrance of NFKB1 variants with respect to the clinical manifestation of CVID is incomplete (about 60% in our cohort, 11 affected subjects among 18 variant carriers), with varied expressivity not only of age at disease onset but also of specific disease manifestations, even within the same pedigree.