GENE SYNTENY IN SPECIES OF PLASMODIUM

We have attempted to establish the degree of linkage conservation betw een different species of the malaria parasite Plasmodium. Initially, t he chromosome locations of 42 homologous genes were established in par asites from a rodent malaria species and the human malaria parasite P. falciparum. Of these genes, 26 appeared to be conserved within ten sy nteny groups between the two genomes. Several synteny groups were anal ysed further by long-range restriction mapping of digested chromosomes . Finally, a fine restriction map of one of the linkage groups was mad e from the rodent malaria parasites P. berghei and from P. falciparum and from the simian malaria parasite P. knowlesi. The fine-scale organ isation of this linkage group appears to have remained intact among th e three species, despite the evolutionary distance between them. This provides the first example of linkage conservation between the rodent, simian and human malaria species, which represent three different bra nches of the inferred phylogenetic tree of the genus Plasmodium. (C) 1 998 Published by Elsevier Science B.V. All rights reserved.