Novel mutations were identified in primary and secondary immunodeifiency patients. Novel NFkB1 heterozygous missense mutations involved in immunedysregulation

Monoallelic mutations in NFKB1 are the most common cause of monogenic primary antibody deficiency (PAD); however, NFKB1 mutations have not been described in rheumatic patients diagnosed with persistent hypogammaglobulinemia following immunomodulatory treatment yet. NFKB1 encodes for the p105 precursor protein, converted into the active transcriptional subunit p50 through proteasomal processing of its C-terminal half upon stimulation and is implicated in the canonical NF-kB pathway. So far, studying the pathogenicity of rare monoallelic NFKB1 variants, including truncating and frameshift mutations, have been shown to cause (haplo)insufficiency, while the functional analysis about missense variants is scarce.