Identification of S315T mutation in katG gene using probe-free exclusive mismatch primers for a rapid diagnosis of isoniazid-resistant Mycobacterium tuberculosis by real-time loop-mediated isothermal amplification

•The katG (S315T) SNP causing INH resistance in TB was detected by LAMP-INH assay.•The assay operates isothermally without using probe or melting curve analysis.•The LAMP primers carry base mismatches to the SNP position of the target sequence.•Rapid diagnosis through end-point electrochemical detection on graphene electrodes.•The assay accommodates testing in high- and low-resource settings.