Haplotype network diagram in Plasmodium falciparum isolates harbouring pfcrt mutation. Network tree is shown according to countries where samples were taken. The haplotype network was constructed for 196 P. falciparum isolates harbouring pfcrt mutation comprises 49 microsatellite haplotypes, based on allelic variations in six microsatellite loci flanking the pfcrt locus (see text for details). The size of each circle corresponds to the number of samples sharing the same haplotype, and the length of an edge is proportional to a variation in repeat number between two haplotypes. IC; Indochina lineage, M; Melanesian lineage, P; Philippine lineage.