NFKBIZ in Psoriasis: Assessing the association with gene polymorphisms and report of a new transcript variant

The IκBζ protein (NFKBIZ gene) is a nuclear inhibitor of NF-κB and plays an important role in the pathogenesis of Psoriasis (Psor). We sought to determine whether common NFKBIZ variants were associated with the risk of developing Psor. A total of 392 patients and 336 controls were genotyped for a common intron 10 indel that could affect pre-mRNA splicing. We found a significantly higher frequency of the insertion among the cw6-positive patients (p = 0.01). Cw6-positive + intron 10 ins/ins were significantly more frequent in the patients (OR = 3.61). The analysis of the cDNA from leukocytes showed a NFKBIZ transcript lacking exon 10, present in all the tested samples. This new alternative transcript lacks a domain predicted to interact with the NFKB1/p50 protein. Functional studies to define the effect of this alternative transcript on the regulation of the NF-κB pathway are necessary.