Fig. 1From: High prevalence of Pfdhfr–Pfdhps quadruple mutations associated with sulfadoxine–pyrimethamine resistance in Plasmodium falciparum isolates from Bioko Island, Equatorial GuineaLinkage disequilibrium (LD) between pairs of single nucleotide polymorphisms (SNPs) located in Pfdhfr and Pfdhps and implicated in drug resistance for Plasmodium falciparum isolates from Bioko Island, Equatorial Guinea. For the Pfdhfr gene, base substitution mutations of T152A, T175C, and G323A are related to single amino acid mutations of N51I, C59R, and S108N, respectively. Similarly, the T1482G, C1486G, A1794G, and G2013T in the Pfdhps gene are related to mutations of S436A, A437G, K540E, and A613S, respectively. According to the four-gamete test, these SNPs are divided into two blocks (black frame). The number in the square indicates a D’ value. The square with dark red and light red indicates a linkage that was statistically significant (P < 0.05). The square with Cambridge blue indicates a linkage is present but is not statistically significant (P > 0.05). The square with white indicates no linkage is presentBack to article page