A 482 base pair gene fragment from samples of amoebae E. histolytica and E. dispar was amplified by PCR. The
amplification products of fragments from the 2 species of amoebae presented differences in mobility in non-denaturing
polyacrylamide gel, probably due to sequence-dependent conformational alterations in the DNA fragments. The method
described here permits E. histolytica and E. dispar to be distinguished with greater sensitivity and rapidity.