All three phenotypes, Pulpal and apical diseases, Pulpitis, and Necrosis of pulp or apical periodontitis, showed the strongest association with variants near HORMAD2 (HORMA domain containing 2) gene in chromosome 22 independently of caries, suggesting that this genetic locus is associated especially with progression of deep caries lesions into endodontic infections. The gene discussed is HORMAD2; the disease is periapical periodontitis.