Abstract: Objective   To analyze genotypes and lactate dehydrogenase（LDH) and esterase(EST) patterns in 10 isolates of Blastocystis hominis collected from Guangxi.  Methods   Ten B. hominis isolates（BhGX1~BhGX10） were obtained from the fecal specimens of patients and cultivated in vitro, and then the genomic DNA was extracted. The isolates were genotyped by PCR using seven pairs of known sequenced-tagged site （STS） primers. Isoenzyme patterns of LDH and EST were investigated by SDS-PAGE.  Results   Out of the 10 isolates, 8 were identified as genotype Ⅰ and the genotypes of the other two （BhGX4 and BhGX7） were unknown which were negative to all the STS primers. Among the ten isolates, 10 LDH bands were found, more with Rm37, Rm49, Rm57, Rm68 and Rm92. 12 bands showed in EST patterns: Rm14, Rm18, Rm23, Rm27, Rm35, Rm41, Rm45, Rm50, Rm55, Rm68, Rm77 and Rm82. Difference existed with the LDH and EST patterns among the isolates.   Conclusion   Genotype Ⅰ is the major one in the 10 B. hominis isolates from Guangxi, and the isolates show different isoenzyme patterns for LDH and EST.

Key words: Blastocystis hominis, Genotype, Isoenzyme, Electrophoresis