title: Impact of 63-bp deletion and single-base mutation in mpt64 gene on M.tb diagnosis.
abstract: After previous research, which selected 180 clinical isolates of the Mycobacterium tuberculosis complex (MTC) from patients in China and performed comparative sequence analysis of the mpt64 gene after amplification and found the polymorphisms of the mpt64 gene in MTC, in order to further investigate the impact of polymorphism of antigen MPT64 on the diagnostic accuracy of MPT64-based test kit, testing on 180 strains by MPT64-based immunochromatographic test (ICT) was conducted. As a result, 180 strains were detected positive except 8 isolates were negative. First, 8 strains harbored 63-bp deletion had a major impact on the biological function of mpt64 and led to the negative results; however, 4 isolates had nonsynonymous nucleotide mutation which led to rare changes in protein structure, did not led to functional change as those 4 strains detected positive by ICT; one strain with a single-base insertion, as the insertion occurred in the last amino acid codon that did not affect T-cell epitopes in MPT64, detected positive by this method. These demonstrate that different mutations in mpt64 gene had impact on diagnostic test kit inconsistently, this was different with some previous studies. And the performance of the mpt64-based diagnostic test kit was still very well with a sensitivity of 95.6% (172/180).
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing 102206, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Qiu
authors.affiliation: Department of Physiology, Xiangya School of Medicine, Central South University Changsha, Hunan 410078, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wan
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing 102206, P. R. China ; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Hangzhou 310003, China.
authors.forename: Haican
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing 102206, P. R. China ; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Hangzhou 310003, China.
authors.forename: Kanglin
authors.initials: K
authors.lastname: Wan
authors.affiliation: Department of Physiology, Xiangya School of Medicine, Central South University Changsha, Hunan 410078, China.
authors.forename: Chaxiang
authors.initials: C
authors.lastname: Guan
authors.affiliation: State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention Beijing 102206, P. R. China ; Department of Physiology, Xiangya School of Medicine, Central South University Changsha, Hunan 410078, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000942:Antigens, Bacterial / Q000235:genetics*; D017353:Gene Deletion; D006801:Humans; D009154:Mutation; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology*
chemical_list: D000942:Antigens, Bacterial; C510537:MPT64 protein, Mycobacterium tuberculosis; D011933:Reagent Kits, Diagnostic
keywords: Mpt64; Mycobacterium tuberculosis; diagnosis; mutation