THE RESA-2 GENE OF PLASMODIUM-FALCIPARUM IS TRANSCRIBED IN SEVERAL INDEPENDENT ISOALTES

The relevance of the ring-infected erythrocyte surface antigen (RESA) of Plasmodium falciparum as a malaria vaccine candidate has been quest ioned of late because RESA-deficient parasites have been found to mult iply normally in culture or in monkeys. The RESA-2 gene was recently d escribed as a pseudogene highly homologous to RESA. In this report, we demonstrate that RESA-2 is not a pseudogene, because we were able to detect RESA-2 transcripts in asexual blood stages of multiple isolates by using polymerase chain reaction on reverse-transcribed mRNA. Trans cription of RESA-2 was observed whether or not the isolates studied ex pressed the RESA protein.