title: Genomic interrogation of ancestral Mycobacterium tuberculosis from south India.
abstract: Mycobacterium tuberculosis is a very important global pathogen. One quarter of the world's TB cases occur in India. The tuberculosis strains isolated from south Indian patients exhibit certain phenotypic characteristics like low virulence in guinea-pigs, resistance to isoniazid, thiophene-2-carboxylic acid hydrazide (TCH) and para-amino salicylic acid (PAS), and enhanced susceptibility to H2O2. Besides this, a large percentage of the isolates harbor only a single copy of IS 6110 which makes these strains distinct. Hence, we have studied the genotypic characteristics of these strains by using advanced techniques like Deletion Micro array, deletion PCR, allelic discrimination RT-PCR using several lineage specific markers and KatG G1388T (non-synonymous) polymorphism along with spoligotyping. The analysis of 1215 tuberculosis patient isolates from south India revealed that 85.2% belonged to the ancestral lineage of M. tuberculosis. Comparative whole-genome hybridization identified six new genomic regions within this lineage that were variably deleted.
authors.affiliation: Tuberculosis Research Centre, Mayor VR Ramanathan Road, Chetput, Chennai, India. sujatha.sujatha36@gmail.com
authors.forename: Sujatha
authors.initials: S
authors.lastname: Narayanan
authors.forename: Sebastien
authors.initials: S
authors.lastname: Gagneux
authors.forename: Lalitha
authors.initials: L
authors.lastname: Hari
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Tsolaki
authors.forename: Suganthi
authors.initials: S
authors.lastname: Rajasekhar
authors.forename: P R
authors.initials: PR
authors.lastname: Narayanan
authors.forename: Peter M
authors.initials: PM
authors.lastname: Small
authors.forename: Susan
authors.initials: S
authors.lastname: Holmes
authors.forename: Kathryn
authors.initials: K
authors.lastname: Deriemer
mesh_terms: D019143:Evolution, Molecular; D017353:Gene Deletion; D016680:Genome, Bacterial; D007194:India; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length