02073nas a2200301   4500000000100000008004100001260001300042653002000055653001900075653001100094653001200105653002500117653003000142653003100172653002600203100001300229700001000242700001000252700001400262700001200276700001200288245012100300856007200421300001100493490000700504520124600511022001401757       2000                            d  c2000 Dec10aAutoradiography10aDNA, Bacterial10aHumans10aleprosy10aMycobacterium leprae10apolymerase chain reaction10aReproducibility of Results10aTrinucleotide Repeats1 aShin Y C1 aLee H1 aLee H1 aWalsh G P1 aKim J D1 aCho S N00aVariable numbers of TTC repeats in Mycobacterium leprae DNA from leprosy patients and use in strain differentiation.  uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC87633/pdf/jm004535.pdf  a4535-80 v383 a<p>Strain differentiation of Mycobacterium leprae would be of great value for epidemiological investigation to identify the infectious sources of leprosy, to understand transmission patterns, and to distinguish between relapse and reinfection. From the M. leprae genome sequence database, TTC DNA repeats were identified. Primer sets designed to amplify the region flanking TTC repeats revealed PCR products of different sizes, indicating that the number of repeats at each locus may be variable among M. leprae strains. The TTC repeats were not found in Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium marinum, or human tissues, which indicated their specificity to M. leprae. Sequence analysis of the TTC repeat region in each of the M. leprae strains showed a variation of 10 to 37 repeats. In the M. leprae strains of 34 multibacillary patients at Cebu, Philippines, M. leprae with 24 and 25 TTC repeats was most common, and this was followed by strains with 14, 15, 20, 21, and 28 repeats. This study thus indicates that there are variable numbers of TTC repeats in a noncoding region of M. leprae strains and that the TTC region may be useful for strain differentiation for epidemiological investigations of leprosy.</p>  a0095-1137