Dendrogram of the pvmsp-1 gene based on the nucleotide acid sequences of 7 allelic variants from 45 P. vivax Anhui isolates and from 52 published sequences around the world in public databases. The tree was constructed using neighbor-joining method implemented in MEGA4 program. The geographical origin of the 52 pvmsp-1 published sequences is as follows: Anhui province (AY465395, AY 465398, AY465400, AY465401, AY465402, AY465405, and AY465406), Liaoning province (JQ319388, JQ582422, JQ390468, JQ606831, JQ606833, and JQ606834), Fujian province (AY538667, AY538668, AY538669, AY538670, AY538671, AY538672, and AY538673), Hainan province (AY465381, AY465377, AY465384, AY465378, AY465383, AY465385, AY465380, and AY465387), and Yunnan province (AY465389, AY465391, AY465392, AY465393, and AY465386) of China, Afghanistan (FJ600704 and FJ600714), Bangladesh (AF435617 and AF435618), India (AY229866 and FJ490829), Iran (FJ619327 and AF502161), Myanmar (EU048259 and EU048266), North Korea (AF216677), Papua New Guinea (DQ376102, DQ376105, and DQ376106), South Korea (HQ171940, JQ317282, and HQ171937), Thailand (GQ890955 and GQ890961), Belem (M60807), and Sal-I (M75674). The length of the line (bottom) is proportional to the genetic differences (%). Numbers on the branches indicate bootstrap proportions (1000 replicates). Only bootstrap values above 50% are displayed on the tree. S: Sal-I type; R: Recombination type.