ABSTRACT
MicroRNAs (miRNAs) are known for their role in mRNA silencing via interference pathways. Repetitive elements (REs) share several characteristics with endogenous precursor miRNAs. In this study, 406 previously identified and 1,494 novel RE-derived miRNAs were sorted from the GENCODE v.19 database using the RepeatMasker program. They were divided into six major types, based on their genomic structure. More novel RE-derived miRNAs were confirmed than identified as RE-derived miRNAs. In conclusion, many miRNAs have not yet been identified, most of which are derived from REs.
Subject(s)
Classification , Interspersed Repetitive Sequences , MicroRNAs , RNA, MessengerABSTRACT
Objective To describe the distribution and spatial clustering of active pulmonary tuberculosis patients in Funing county of Jiangsu Province,China,and to determine the rules of recent transmission in TB patients and help establish the strategy of TB control with the results of genetic typing of Mycobacterium tuberculosis (M.TB).Methods Newly reported and retreated tuberculosis patients registered in Funing county,Jiangsu Province between Jun 1,2009 and Nov 30,2010 were recruited as research subjects.Geographic information system was applied to analysis the spatial clustering of tuberculosis patients.The M.TB isolates were genotyped by mycobacterial interspersed repetitive units (MIRU).Cluster was defined as two or more patients' M.TB isolates harboring identical MIRU genotype.Results During the study period,there were a total of 681 active pulmonary tuberculosis patients reported.Global Moran's I value and local Moran's I value indicated a random and sporadical manner instead of global spatial clustering of tuberculosis patients in Funing county.Spatial scan statistics (SaTScan) showed that the patients in Guoshu town was statistically significant in spatial clustering (RR=1.85,P=0.036).Among 169 strains of M.TB,27 strains distributed in 12 clusters,which indicated recent transmission among patients within the cluster.Conclusions In rural areas with high tuberculosis incidence,it is less likely to have massive tuberculosis outbreak.Sporadic transmission of tuberculosis may have played an important role in the transmission of tuberculosis in high prevalence area.
ABSTRACT
BACKGROUND: Mycobacterial Interspersed Repetitive Units (MIRUs) that are located mainly in intergenic regions dispersed throughout the Mycobacterium tuberculosis genome. The selected MIRU loci, which were composed of a 12-locus set, demonstrated a high power for discrimination of Mycobacterium tuberculosis isolates collected from Kangwon province of Korea. To evaluate its ability to discriminate the M. tuberculosis strains, 45 clinical isolates were genotyped using the methods IS6110 RFLP and MIRU. METHODS: All the samples were collected during the period from January 2007 to December 2007 from TB patients, who were residents and registered to a public health center of Kangwon Province in Korea. A total of 45 DNAs were extracted from clinical isolated mycobacterial strains and genotyped using IS6110 RFLP, the MIRU method. RESULTS: We compared the 12-MIRU with IS6110 RFLP in the 45 samples, the 12-locus version offered less discriminatory power (Hunter-Gaston discriminatory index [HGDI]: 0.959 vs 0.998; 57.78% of clustered cases vs 8.89%). CONCLUSION: This 12-locus MIRU can be useful when additional combinations of other loci for genotyping M. tuberculosis in Korea where the Beijing family strains are dominant.