Analysis on the Genotyping of 70 Mycobacterium Tuberculosis Clinical Strains Isolated from Zhejiang Province with Spoligotyping

Objective To explore the distribution of relative genotypes of Mycobacterium tuberculosis (M.tuberculosis) clinical isolates in Zhejiang province and the association between Beijing family genotype and drug resistance.Methods M. tuberculosis clinical isolates collected from Zhejiang province were cultured with Lowenstein-Jensen medium and genotyped with spacer oligonucleotide typing (Spoligotyping).The clustering of genotype was analyzed with BioNumcrics (Version 5.0).Chi- square test was used for statistical analysis.Results By spoligotyping,70 strains were categorized into two groups,Beijing family which occupied 70% (49/70) and non-Beijing family which occupied 30% (21/70).The two groups were divided in- to 18 genotypes in which 12 strains carded 12 unique genotypes and other 58 ones carded 6 genotypes.In Beijing family strains 89.8 % (44/49) were typical Beijing family strains.There were more polymorphisms in Non-Beijing family strains in which 21 strains could be subdivided into 13 genotypes including 9 unique gcnotypes.71.4 % (35/49) of Beijing family strains were sen- sitive strains and 28.6 % (14/49) were drug resistant strains,while 66.7% of Non-Beijing family strains were sensitive strains and 33.3% were drug resistant.There was no significant difference between them (X~2=0.158,P0.05).Conclu- sion Beijing family strain was predominant strain of M.tuberculosis in Zhcjiang province.There was no obvious association be- tween Beijing family genotype and drug resistance.