Table 2.
Distribution of COX-2 variants
| Variants | Total Population n (%) | Aparasitemic (MPS-) n (%) | Non-SMA (Hb ≥ 5.0 g/dL) n (%) | SMA (Hb < 5.0 g/dL) n (%) | P value | ||
|---|---|---|---|---|---|---|---|
| −512 | |||||||
| CC | 921 (85.2) | 217 (83.1) | 578 (86.3) | 126 (84.0) | 0.180a | ||
| CT | 139 (12.9) | 42 (16.1) | 76 (11.3) | 21 (14.0) | |||
| TT | 21 (1.9) | 2 (0.8) | 16 (2.4) | 3 (2.0) | |||
| MAF (p/q) | 0.916/0.084 | 0.912/0.088 | 0.919/0.081 | 0.911/0.089 | |||
| HWE (X2, P) | 28.327, <0.001 | 0.984, <0.001 | 36.877, <0.001 | 3.167, 0.075 | |||
| −608 | |||||||
| TT | 748 (69.2) | 186 (71.3) | 457 (68.2) | 105 (70.0) | 0.664a | ||
| TC | 277 (25.6) | 59 (22.6) | 179 (26.7) | 39 (26.0) | |||
| CC | 56 (5.2) | 16 (6.1) | 34 (5.1) | 6 (4.0) | |||
| MAF (p/q) | 0.820/0.180 | 0.826/0.174 | 0.816/0.184 | 0.830/0.170 | |||
| HWE (X2, P) | 18.746, 0.001 | 12.038, 0.001 | 8.335, 0.004 | 0.928, 0.335 | |||
| −765 | |||||||
| GG | 475 (43.9) | 113 (43.3) | 297 (44.3) | 65 (43.3) | 0.148a | ||
| GC | 450 (41.6) | 103 (39.5) | 275 (41.0) | 72 (48.0) | |||
| CC | 156 (14.4) | 45 (17.2) | 98 (14.6) | 13 (8.7) | |||
| MAF (p/q) | 0.648/0.352 | 0.630/0.370 | 0.649/0.351 | 0.673/0.327 | |||
| HWE (X2, P) | 8.375, 0.004 | 6.130, 0.013 | 6.657, 0.010 | 1.246, 0.264 | |||
| −1195 | |||||||
| AA | 973 (90.0) | 239 (91.6) | 595 (88.8) | 135 (92.7) | 0.271a | ||
| AG | 91 (8.4) | 17 (6.5) | 63 (9.4) | 11 (7.3) | |||
| GG | 17 (1.6) | 5 (1.9) | 12 (1.8) | 0 (0.0) | |||
| MAF (p/q) | 0.942/0.058 | 0.948/0.052 | 0.935/0.065 | 0.962/0.038 | |||
| HWE (X2, P) | 55.863, 0.001 | 29.471, 0.001 | 34.095, 0.001 | 0.224, 0.363 | |||
| Haplotypes | |||||||
| CTGA | 0 | 391 (36.2) | 100 (38.3) | 248 (37.0) | 43 (28.7) | 0.112a | |
| 1 | 690 (63.8) | 161 (61.7) | 422 (63.0) | 107 (71.3) | |||
| CCGA | 0 | 777 (71.9) | 195 (74.7) | 476 (71.0) | 106 (70.7) | 0.502a | |
| 1 | 304 (28.1) | 66 (25.3) | 194 (29.0) | 44 (29.3) | |||
| CTCA | 0 | 590 (54.6) | 137 (52.5) | 367 (54.8) | 86 (57.3) | 0.629a | |
| 1 | 491 (45.4) | 124 (47.5) | 303 (45.2) | 64 (42.7) | |||
| CTCG | 0 | 1072 (99.2) | 260 (99.6) | 662 (98.8) | 150 (100.0) | 0.228b | |
| 1 | 9 (0.8) | 1 (0.4) | 8 (1.2) | 0 (0.0) | |||
| TTCA | 0 | 952 (88.1) | 228 (87.4) | 597 (89.1) | 127 (84.7) | 0.292a | |
| 1 | 129 (11.9) | 33 (12.6) | 73 (10.9) | 23 (15.3) | |||
| TTGG | 0 | 1076 (99.5) | 260 (99.6) | 668 (99.7) | 148 (98.7) | 0.235b | |
| 1 | 5 (0.5) | 1 (0.4) | 2 (0.3) | 2 (1.3) | |||
| CCCA | 0 | 1,046 (96.8) | 250 (23.1) | 648 (96.7) | 148 (98.7) | 0.281a | |
| 1 | 35 (3.2) | 11 (4.2) | 22 (3.3) | 2 (1.3) | |||
| TTGA | 0 | 1059 (98.0) | 254 (97.3) | 657 (98.1) | 148 (98.7) | 0.622b | |
| 1 | 22 (2.0) | 7 (|2.7) | 13 (1.9) | 2 (1.3) | |||
| CTGG | 0 | 993 (91.9) | 242 (92.7) | 610 (91.0) | 141 (94.0) | 0.412a | |
| 1 | 88 (8.1) | 19 (7.3) | 60 (9.0) | 9 (6.0) | |||
| TCGA | 0 | 1077 (99.6) | 259 (99.2) | 668 (99.7) | 150 (100.0) | 0.414a | |
| 1 | 4 (0.4) | 2 (0.8) | 2 (0.3) | 0 (0.0) | |||
| CCGG | 0 | 1075 (99.4) | 260 (99.6) | 665 (99.3) | 150 (100.0) | 0.491b | |
| 1 | 6 (0.6) | 1 (0.4) | 5 (0.7) | 0 (0.0) | |||
| TTCG | 0 | 1075 (99.4) | 261 (100.0) | 664 (99.1) | 150 (100.0) | 0.157b | |
| 1 | 6 (0.6) | 0 (0.0) | 6 (0.9) | 0 (0.0) | |||
Data are presented as proportions [n (%)] of genetic variants within the study groups. Children (n = 1081) were categorized into aparasitemic controls (n = 261; no parasitemia) and based on WHO definition of SMA into either non-SMA (n = 670; Hb ≥ 5.0 g/dL) or SMA (n = 150; Hb < 5.0 g/dL). Minor Allele frequencies (MAF; p/q) were computed for variants within study groups. Hardy–Weinberg Equilibrium (HWE) was computed using a χ2 goodness of fit test. Haplotypes were constructed using the HPlus software program (Fred Hutchinson Cancer Research Center, WA, USA), and their distribution frequencies estimated using haploview software (version 4.2; Broad Institute, MA, USA). (0) = non-carriers of haplotypes and (1) = carriers of haplotypes.
Statistical significance determined by Pearson’s χ2 test.
Statistical significance determined by Fisher’s exact tests