Background
Methods
Study area and studied populations
Collection sites and GPS positions | Pygmies | Bantus | ||
---|---|---|---|---|
Number of samples | Number of P. falciparum infections (prevalence %) | Number of samples | Number of P. falciparum infections (prevalence %) | |
Isolated Pygmy villages | ||||
Bitouga (2°07.133′N, 12°07.770′E) | 21 | 13 (62) | 0 | – |
Etho (2°05.728′N, 12°09.460′E) | 28 | 9 (32) | 0 | – |
Mixed villages | ||||
Doumassi (2°09.212′N, 12°07.781′E) | 32 | 13 (40.6) | 5 | 1 (20) |
Zangaville (2°04.474′N, 12°02.476′E) | 13 | 5 (38.4) | 10 | 6 (60) |
Esseng (2°09.726′N, 12°08.321′E) | 54 | 30 (55.5) | 0 | – |
NkokAkom (2°10.900′N, 12°07.826′E) | 11 | 8 (72.7) | 12 | 5 (41.6) |
Mimbang (2°11.593′N, 12°07.620′E) | 11 | 7 (63.6) | 11 | 8 (72.7) |
Forestry villages | ||||
TTIB (1°36. 201′N, 11°59. 986′E) | 0 | – | 56 | 39 (69.6) |
Bordamure (1°02.305′N, 11°41.629′E) | 0 | – | 39 | 21 (53.8) |
STIBG (1°00.472′N, 11°55.789′E) | 0 | – | 39 | 31 (79.4) |
Total | 170 | 85 (50) | 172 | 111 (64.5) |
Determination of Plasmodium falciparum infections
Molecular genotyping of Plasmodium falciparum isolates
Plasmodium falciparum population genetic analyses
Results
Malaria prevalence and Plasmodium species
Microsatellite population structure
Isolated pygmyvillages (IPV) | Mixed villages (MV) | Forestry villages (FV) | All pygmies | All bantus | ||
---|---|---|---|---|---|---|
Pygmies | Bantus | |||||
Microsatellites | ||||||
Ta60 | 0.835 | 0.817 | 0.828 | 0.789 | 0.826 | 0.808 |
Ara2 | 0.833 | 0.877 | 0.889 | 0.853 | 0.855 | 0.871 |
Taa87 | 0.819 | 0.847 | 0.916 | 0.832 | 0.833 | 0.874 |
Pfpk2 | 0.930 | 0.808 | 0.889 | 0.890 | 0.869 | 0.890 |
Polyα | 0.944 | 0.899 | 0.932 | 0.891 | 0.922 | 0.912 |
Ta1 | 0.944 | 0.929 | 0.941 | 0.848 | 0.937 | 0.894 |
Taa81 | 0.814 | 0.834 | 0.792 | 0.835 | 0.824 | 0.814 |
Mean | 0.874 | 0.859 | 0.884 | 0.848 | 0.866 | 0.866 |
Candidate genes | ||||||
MSP2 | 0.711 | 0.836 | 0.603 | 0.741 | 0.773 | 0.672 |
MSP1 | 0.821 | 0.718 | 0.829 | 0.724 | 0.769 | 0.776 |
EBA-175 | 0.220 | 0.361 | 0.423 | 0.384 | 0.291 | 0.404 |
GLURP | 0.359 | 0.741 | 0.612 | 0.644 | 0.550 | 0.628 |
Mean | 0.528 | 0.664 | 0.617 | 0.623 | 0.596 | 0.620 |
Group | Village | Isolated Pygmy villages | Mixed villages | Forestry Villages | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pygmies | Pygmies | Pygmies | Pygmies | Bantus | Pygmies | Bantus | Pygmies | Bantus | Bantus | Bantus | Bantus | |||
Etho | Doumassi | Esseng | Mimbang | Mimbang | NkokAkom | NkokAkom | Zangaville | Zangaville | Bordamure | STIBG | TTIB | |||
Microsatellites | ||||||||||||||
Isolated Pygmy villages | Pygmies | Bitouga | −0.0256 | −0.0101 | −0.0033 | −0.0068 | −0.0016 | −0.0005 | −0.039 | 0.0075 | −0.0217 | 0.0075 | 0.0025 | −0.0017 |
Pygmies | Etho | −0.0138 | −0.0168 | 0.0162 | −0.0135 | −0.0175 | −0.033 | −0.0117 | −0.0212 | 0.008 | 0.0045 | −0.0073 | ||
Mixed villages | Pygmies | Doumassi | −0.0069 | −0.0175 | 0.0116 | −0.0035 | −0.0188 | 0.0392 | −0.0301 | 0.0277 | 0.0058 | 0.02 | ||
Pygmies | Esseng | −0.0022 | 0.0146 | 0.0164 | −0.0166 | −0.0202 | −0.0138 | 0.0151 | 0.0113 | 0.0141 | ||||
Pygmies | Mimbang |
−0.0015
| 0.0056 | −0.0233 | 0.0057 | 0.0037 | 0.0164 | 0 | 0.0228 | |||||
Bantus | Mimbang | −0.0036 | −0.0046 | −0.0232 | 0.0156 | 0.0563 | 0.0142 | 0.0319 | ||||||
Pygmies | NkokAkom |
−0.02
| 0.0204 | 0.0163 | 0.0167 | 0.025 | 0.0139 | |||||||
Bantus | NkokAkom | −0.0431 | −0.0202 | −0.0281 | −0.0204 | −0.0311 | ||||||||
Pygmies | Zangaville |
−0.0277
| 0 | −0.0065 | −0.007 | |||||||||
Bantus | Zangaville | 0.0025 | −0.0087 | −0.001 | ||||||||||
Forestry villages | Bantus | Bordamure | 0.0144 | 0.0054 | ||||||||||
Bantus | STIBG | 0.01 | ||||||||||||
Candidate genes | ||||||||||||||
Isolated Pygmy villages | Pygmies | Bitouga | −0.0417 | 0.0421 | 0.1063 | 0.1041 | 0.1398 | 0.0372 | 0.2664* | 0.149 | 0.1301 | 0.1632 | 0.1509* | 0.1428 |
Pygmies | Etho | 0.0027 | 0.0795 | 0.0244 | 0.1629 | 0.0272 | 0.2818 | 0.0324 | 0.0543 | 0.1335 | 0.1627* | 0.1245 | ||
Mixed villages | Pygmies | Doumassi | 0.0469 | −0.0436 | 0.0255 | −0.064 | 0.1047 | −0.0423 | −0.0001 | 0.0128 | 0.114* | 0.0194 | ||
Pygmies | Esseng | 0.1123 | 0.1308 | 0.1079 | 0.2229* | −0.0417 | 0.0472 | 0.065 | 0.0752 | 0.1047* | ||||
Pygmies | Mimbang |
0.0236
| −0.1455 | 0.0874 | 0.0718 | −0.0164 | 0.0557 | 0.0987 | 0.0616 | |||||
Bantus | Mimbang | −0.0626 | 0.0374 | 0.0465 | 0.064 | 0.088 | 0.0498 | 0.0471 | ||||||
Pygmies | NkokAkom |
0.0754
| 0.1014 | 0.0076 | 0.0031 | 0.0273 | 0.0278 | |||||||
Bantus | NkokAkom | 0.2069 | 0.1619 | 0.1916 | 0.1838* | 0.1617 | ||||||||
Pygmies | Zangaville |
−0.0312
| −0.0239 | 0.1373 | −0.0645 | |||||||||
Bantus | Zangaville | 0.0622 | 0.1055 | 0.0735 | ||||||||||
Forestry villages | Bantus | Bordamure | 0.1085 | 0.0272 | ||||||||||
Bantus | STIBG | 0.1612* |
Distance | Within/between ethnies | Within/between village types | |
---|---|---|---|
Microsatellites | 0.387** | −0.145 ns | −0.15 ns |
MSP2 | 0.258 ns | 0.0156 ns | 0.15 ns |
MSP1 | 0.08 ns | −0.06 ns | −0.23 ns |
EBA-175 | 0.025 ns | −0.05 ns | 0.02 ns |
GLURP | 0.025 ns | 0.09 ns | 0.54** |
All candidate genes | 0.197 ns | 0.11 ns | 0.39** |