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Background and Objective: The emergence of drug resistance in Mycobacterium tuberculosis and especially drug resistant strains has created problems for the treatment of tuberculosis control, worldwide. This study was performed to evaluate the changes in N-acetyltransferase (NAT) pattern of methylsonone in patients who did not respond to first-line treatment for Mycobacterium tuberculosis.
Methods: This descriptive-analytical study was performed on 200 patients with tuberculosis. After preparing the blood sample, saturated salt method was used to extract DNA. For the determination of quantity and quality of DNA, two methods of spectrophotometry and electrophoresis on agarose gel were used. The methylation pattern of NAT1 gene was investigated by HRM method.
Results: 34 patients were resistant to the first line of treatment. 18 patients showed hypermethylation pattern, 12 patients showed non-methylated pattern and 4 patients showed hypomethylated pattern. 166 patients were not resistant to the first line, of which 23 patients in hypermethylated group, 120 patients in group Non-methylated and 23 patients were in the hypomethylated row. There was a statistically significant relationship between methylation level and drug resistance (P<0.05).
Conclusion: This study showed that resistance to first-line treatment of Mycobacterium tuberculosis was related to the level of N-acetyltransferase gene methylation.