Characterization of the metacaspase 1 gene in Plasmodium vivax field isolates from southern Iran and Italian imported cases.

Plasmodium vivax is still the more prevalent human Plasmodium outside Africa and despite this fact, there is still a deep lack of knowledge on its biology. Metacaspases are cysteine proteases related to metazoan caspases, involved in programmed cell death. Here, we have characterized the P. vivax metacaspase 1 gene in a total of 63 vivax isolates, 32 isolates collected in southern Iran and 31 Italian imported isolates originating from 12 different endemic countries. We have firstly identified DNA size polymorphism in P. vivax metacaspase 1 gene. A total of four different allelic sizes were found, resulting from the insertion of 1 to 4 tandem repeat units located within the intronic region of the P. vivax metacaspase 1. Similarly, we also have identified four distinct allelic types by using vivax merozoite surface protein-1 size polymorphism analysis.