Knowledge of strain diversity is important for better understanding of epidemiology of infection and guiding disease control programs. Johne's disease (JD) is endemic in the domestic livestock, but India lacks countrywide investigations on prevalence of JD (Singh et al., 2007, Kumar et al.,2007, Sharma et al., 2007). Preliminary geno-typing of MAP from humans, cattle, goats, buffaloes, sheep and blue bulls located at CIRG and Mathura region of North India, revealed presence of same 'Bison type' genotype (Sevilla et al., 2005, 2007, Singh et al., 2005 b, c, Whittington, 2001). This work aimed to study the degree of diversity in Indian 'Bison type' isolates from different animal species, using more discriminatory genotyping tools (Short sequence repeat, SSR). Two loci Mononucleotide G repeat (AK46234) and tri-nucleotide GGT repeat (CAB06859) being most discriminatory SSRs (Amonsin et al., 2004) were selected for fingerprinting of native isolates. Purified PCR products were sequenced using Big Dye Terminator (BDT) chemistry and sequence analyzed using DNA sequencer ABI prisms 3700 DNA analyzer. Quality of sequencing data was analyzed using ABS sequence scanner v1.0 software and number of repeats at each locus for each isolate was determined.

All MAP isolates yielded detectable PCR product for G and GGT repeat loci. Sequence analysis of these 2 loci revealed that all isolates recovered from different host species were having same profile of SSR repeats, 7 G and 4 GGT (7g4ggt). No allelic variation among the isolates may be an indicative of interspecies transmission of Indian MAP 'Bison type' genotype among domestic and wild ruminant species (cattle, goat, sheep, buffaloes and blue bulls), located at CIRG campus and in the Mathura region of North India. Clinical data from our study indicate that Indian MAP 'Bison type' genotype is highly pathogenic for both domestic and wild ruminants (Hajra et al., 2005, Yadav et al., 2007, Kumar et al., 2007, Singh et al., 2005, Singh, 1998).