This study is the first to suggest a possible molecular mechanism that may explain the rare co-occurrence of CdLS and psoriasis: RAD21 deficiency disrupts chromatin architecture and immune gene regulation, while TNFAIP3 loss-of-function removes critical NF-κB inhibition, resulting in synergistic developmental and inflammatory phenotypes. This evidence concerns the gene TNFAIP3 and Cornelia de Lange syndrome.