Fig. 3
Sliding window plots of d N/d S ratio for Plasmodium falciparum surf 4.1 sequence encoding extracellular region. Data obtained in this study for western Kenyan isolates (n = 24) is plotted with a solid red line. As a comparison, previously published surf 4.1 sequences from eastern Kenya [15] and Thai [17] are plotted with a solid cyan line and a dotted black line, respectively. Asterisks indicate a part of Var1 region and Var2 region where d N was significantly higher than d S in two Kenyan parasite populations (p < 0.05). Nucleotide positions are after 3D7 line sequence. Window length is 90 bp and step size is 3 bp. A scheme of SURFIN4.1 extracellular region (bottom) are shown to visualize the location of the peaks. N-terminal (N), Cys-rich domain (CRD), and variable regions 1 and 2 (Var1 and Var2)