Interestingly, in the human gingival epithelia, Cx43 expression showed a progressive decrease from the spinous layers of the oral gingival epithelium to the sulcular epithelium and parts of the junctional epithelium.102,103 Cx26 was detected in the granular cell layer and lower part of the squamous cell layer.105 Nevertheless, Cx43 was downregulated at the early stage of gingival wound healing, which may contribute to the fast wound healing of the gingival tissue.106 However, to the best of our knowledge, no information is available on the role of gap junctions in periodontal disease. The gene discussed is GJA1; the disease is periodontal disorder.