Leishmaniasis is one of the important tropical diseases in the world. Although it is not prevalent in Korea, imported cases have been recorded. The karyotype of Leishmania sp. has been observed to be variable by localities or by strains, but the karyotype of a strain is known to be stable. This study was performed to observe if the karyotype of a Leishmania sp. would be changed under some stressful conditions. The karyotype, analyzed by pulsed field gradient gel electrophoresis, was not grossly changed by heat shock, chemotherapeutics, UV illumination, and gamma irradiation. Radiation destroyed the chromosomes mechanically, but subcultured organisms after irradiation showed unaffected karyotype. The present findings suggest that the karyotype of a Leishmania strain is so stable that it is not altered by temporary stimulation with heat, drugs, and radiation.
