Genetic diversity and population structures of Plasmodium falciparum parasites imported to China from Central and West Africa determined using a SNP barcode.

BACKGROUND: Malaria remains a highly threatening infectious disease, with Africa being the main epidemic area. China has achieved the notable feat of eliminating malaria domestically, yet the looming threat of imported malaria cases remains a concern. This study aims to apply the SNP barcode technology to investigate the population structure of P. falciparum imported to China from Central and West Africa. METHODS: We applied a 24-SNP high-resolution melting (HRM) barcode to analyze the diversity of P. falciparum populations imported to China from Central and West Africa. RESULTS: A total of 181 samples were analyzed using HRM assay to obtain a complete 24-SNP barcode. There was no significant difference in the proportion of multi-clone infections among the four populations. The level of nucleotide diversity observed across all four populations is low. The observed pairwise FST values ranged from 0.001 to 0.054, indicating a low to moderate level of genetic differentiation between the four populations. The combined results of principal component analysis and population structure assessment reveal a lack of prominent clustering among the four populations. CONCLUSIONS: The present study validated the potential of the 24-SNP HRM barcode in examining diversity and variations in imported P. falciparum populations. Our studies confirmed that this barcode is insufficient for distinguishing isolates from Central and West Africa, potentially due to the minimal genetic differentiation among P. falciparum populations in these regions.