High concordance of Pfdhfr and Pfdhps genotypes between matched peripheral and placental isolates of delivered women in Bobo-Dioulasso, Burkina Faso

Whether maternal peripheral parasites constitute a representative sample of the overall population
infecting the individual, remains unknown in Burkina Faso. We therefore compared Pfdhfr and Pfdhps génotypes between matched peripheral and placental isolates. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of polymorphic codons of the Pfdhfr gene (51, 59, 108 and 164) and the Pfdhps gene (437 and 540) was performed in 18 matched peripheral and placental dried blood spots of delivered women in Bobo-Dioulasso. Both Pfdhfr and Pfdhps genes were successfully genotyped in 94.4% (17/18) of the matched samples. Only 8.8% (3/34) of génotypes were of the wild type, while 20.6% (7/34), 20.6% (7/34), 23.5% (8/34) and 26.5% (9/34) comprised one, two, three and four mutations, respectively. None of the samples carried both Pfdhfr I164L and Pfdhps K540E mutations. A concordance of 82.4% was observed in matched samples for both the Pfdhfr and Pfdhps genes. Setting placental allèles as the reference, a concordance of 100% was obtained with Pfdhfr mutation S108N, Pfdhfr mutation C59R+S108N, and Pfdhfr mutation N51I+C59R +S108N, respectively. Likewise, a concordance of 85.7% was observed with the Pfdhps
mutation A437G. For epidemiological purposes, peripheral blood Pfdhfr and Pfdhps genotyping is sufficient for monitoring SP resistant molecular markers in pregnant women.