DIRECT PCR AMPLIFICATION AND SEQUENCE-ANALYSIS OF EXTRACHROMOSOMAL PLASMODIUM DNA FROM DRIED BLOOD SPOTS

The Plasmodium parasite possesses two extrachromosomal genomes; the mi tochondrial genetic element and the extrachromosomal plastid-like DNA. The latter has only been fully described for one culture strain of P. falciparum. In this study, a rapid procedure for amplifying plastid D NA from dried blood spots of blood infected with different malaria spe cies was developed. PCR amplification of a 595 bp fragment within the plastid-like large subunit ribosomal-RNA (LSU-rRNA) gene was achieved using primers derived from the P. falciparum sequence. The PCR product was observed in all Plasmodium species examined. Sequence analysis of amplified products homologous to an LSU-rRNA fragment of the plastid- like extrachromosomal circle revealed extensive conservation between P lasmodium species including P. falciparum, P. vivax, P. malariae and P . berghei. (C) 1997 Elsevier Science B.V.