Complementing this, psoriasis susceptibility variants in IL12B (rs3212227, rs6887695) strengthen IL-23/Th17 signaling that sustains cutaneous inflammation and align with the clinical efficacy of p40 blockade (ustekinumab), whereas in AD, IL12B variation tracks with IL-12–dependent neuroinflammatory cascades and experimental evidence that p40 can exacerbate amyloid pathology in neural cells [38,39,40]. This evidence concerns the gene IL12B and Alzheimer disease.