Current understanding of the Mycobacterium avium subsp. paratuberculosis genetic diversity in Iran, studied by RFLP-IS900

Introduction and Objectives: In Iran, paratuberculosis has been long a frequently-diagnosed disease in cattle and sheep and goat herds. Only little is known on genotypic variation of the Mycobacterium avium subsp. paratuberculosis (MAP) population in this country. So the resent study surveyed genetic diversity of an Iranian isolates using RFLP-IS900. Materials and Methods: In the present study, 46 archived bovines, ovine and caprine indigenous MAP isolates (representing four municipal provinces) plus two laboratory strains of MAP 316F and III & V were sub-cultured on plain mycobactin J-supplemented Herrold s egg-yolk slants. All the recovered isolates/strains were subsequently subjected to IS900 RFLP analysis using PstI. Results: Totally, ten RFLP patterns were identified with three of them singletons and seven shared types. The identical RFLP type shown by both MAP 316F and III & V strains was categorically different from that of the Iranian field isolates. The largest pattern, represented by 22 isolates, recovered from bovine and caprine. This specific pattern is highly similar to type circulating G, then type B represented by 11 isolates, recovered from all the three animals. Such lack of difference observed in the Iranian environment, is very likely to indicate that the most frequent MAP strains can infect multiple host species. Conclusion: More study on genetic diversity of MAP in Iran urges using restriction fragment length polymorphism and alternative genotyping system.

Keywords:

paratuberculosis , PstI , Restriction Fragment Length Polymorphism