02582nas a2200481   4500000000100000008004100001653001600042653001300058653003000071653002500101653001300126653002400139653000900163653000900172653002300181653001100204653004200215653001900257653002100276653002300297653001200320653002400332653001000356100001400366700001100380700001100391700001200402700001400414700001200428700001500440700001200455700001200467700001400479700001200493700001500505700001900520245010900539856005100648300001100699490000700710520136900717022001402086       2016                            d10aYoung Adult10aRifampin10apolymerase chain reaction10aMycobacterium leprae10aMutation10aMice, Inbred BALB C10aMice10aMale10aLeprostatic Agents10aHumans10aGene Expression Regulation, Bacterial10aDNA, Bacterial10aBiological Assay10aBacterial Proteins10aAnimals10aAmino Acid Sequence10aAdult1 aLavania M1 aHena A1 aReja H1 aNigam A1 aBiswas NK1 aSingh I1 aTurankar R1 aGupta U1 aKumar S1 aRewaria L1 aPatra P1 aSengupta U1 aBhattacharya B00aMutation at codon 442 in the rpoB gene of Mycobacterium leprae does not confer resistance to rifampicin.  uhttps://leprosyreview.org/article/87/1/09-3100  a93-1000 v873 a<p><strong>BACKGROUND: </strong>Rifampicin is the major drug in the treatment of leprosy. The rifampicin resistance of Mycobacterium leprae results from a mutation in the rpoB gene, encoding the β subunit of RNA polymerase. As M. leprae is a non-cultivable organism observation of its growth using mouse food-pad (MFP) is the only Gold Standard assay used for confirmation of "in-vivo" drug resistance.</p>

<p><strong>OBJECTIVE: </strong>Any mutation at molecular level has to be verified by MFP assay for final confirmation of drug resistance in leprosy.</p>

<p><strong>MATERIAL AND METHODS: </strong>In the present study, M. leprae strains showing a mutation only at codon 442 Gln-His and along with mutation either at codon 424 Val-Gly or at 438 Gln-Val within the Rifampicin Resistance Determining Region (RRDR) confirmed by DNA sequencing and by high resolution melting (HRM) analysis were subjected for its growth in MFP.</p>

<p><strong>RESULT AND CONCLUSION: </strong>The M. leprae strain having the new mutation at codon 442 Gln-His was found to be sensitive to all the three drugs and strains having additional mutations at 424 Val-Gly and 438 Gln-Val were conferring resistance with Multi drug therapy (MDT) in MFP. These results indicate that MFP is the gold standard method for confirming the mutations detected by molecular techniques.</p>
  a0305-7518