Plasmodium falciparum genome-wide scans for positive selection, recombination hot spots and resistance to antimalarial drugs

Xin-zhuan Su and colleagues report genome-wide SNP genotyping of 189 culture-adapted Plasmodium falciparum parasites and examine population structure, selection and recombination hotspots. They also conduct genome-wide association studies for resistance to seven different antimalarial drugs. Antimalarial drugs impose strong selective pressure on Plasmodium falciparum parasites and leave signatures of selection in the parasite genome1,2; screening for genes under selection may suggest potential drug or immune targets3. Genome-wide association studies (GWAS) of parasite traits have been hampered by the lack of high-throughput genotyping methods, inadequate knowledge of parasite population history and time-consuming adaptations of parasites to in vitro culture. Here we report the first Plasmodium GWAS, which included 189 culture-adapted P. falciparum parasites genotyped using a custom-built Affymetrix molecular inversion probe 3K malaria panel array with a coverage of ∼1 SNP per 7 kb. Population structure, variation in recombination rate and loci under recent positive selection were detected. Parasite half-maximum inhibitory concentrations for seven antimalarial drugs were obtained and used in GWAS to identify genes associated with drug responses. This study provides valuable tools and insight into the P. falciparum genome.