Current guidelines emphasize a triad for PTB diagnosis: endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) demonstrating caseating granulomas, cartridge-based nucleic acid amplification testing (CBNAAT) with a sensitivity of 92%, and elevated cystic fluid adenosine deaminase (ADA) >35 U/L [7-10]. The gene discussed is ADA; the disease is Granuloma.