The glyA gene in Tannerella forsythia is attributed for its virulence by producing the enzyme serine hydroxymethyltransferase (SHMT), which plays a vital role in bacterial cell metabolism.The study is thus aimed to determine the frequency of the glyA gene from the clinical strains of T. forsythia isolated from periodontitis patients.Forty-five patients with varying degrees of periodontitis were included in the study, and the plaque samples collected from them were anaerobically processed by inoculating onto sterile anaerobic blood agar plates using a gaspak system, with incubation at 37°C for 5-7 days. The DNA was extracted from the obtained isolated colony, and PCR was performed to confirm the presence of the glyA gene.In total, 46.6% (n = 7) of the cases in group III aggressive periodontitis (n = 15) and 6.66% (n = 1) in group II stage II periodontitis (n = 15) showed the presence of T. forsythia, and among them, 57.14% (n = 4) showed the presence of the glyA gene. Conclusion: The findings of the study showed that the glyA gene may be associated with the pathogenesis of T. forsythia and could be thus a novel candidate for the future theragnostic approach to combat periodontitis.