Fig. 1

Frequencies of msp1 block 2 major allelic types vary by geographical region. Alignment of short read data from 2400 Pf3k samples to the msp1 block 2 reference library was used to determine the presence of K1- (red), MAD20- (blue) and RO33-like (green) msp1 block 2 alleles in each sample, enabling a total of 3815 allele counts to be made (46% of the samples had multiple alleles detected). a Pie diagrams show overall frequencies in the samples from each continent. b The frequencies of each allelic type are shown for each sampling site where more than 30 samples were sequenced