Table 3 Meta-analyses of the association between the 5-HTTLPR polymorphism and the presence of IBS
| Â | Ethnicity | Cases/Controls | LS vs SS | Â | Â | LL vs LS/SS | Â | Â | LL/LS vs SS | Â | Â |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Â | Â | Â | (OR,95% CI) | P(Model) | Bon | (OR,95% CI) | P(Model) | Bon | (OR,95% CI) | P(Model) | Bon |
IBS | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 25 studies | Overall | 3443/3359 | (0.814,0.681-0.973) | P = 0.023 (R) | 0.138 | (1.141,0.935-1.391) | P = 0.195 (R) | 1.000 | (0.883,0.739-1.055) | P = 0.171 (R) | 1.000 |
 11 studies | Cau/M Cau | 1855/1590 | (0.796,0.566-1.119) | P = 0.189 (R) | 1.000 | (1.506,1.112-2.039) | P = 0.070 (F) | 0.420 | (0.874,0.643-1.189) | P = 0.391 (R) | 1.000 |
 9 studies | East Asian | 1138/1102 | (0.892,0.727-1.094) | P = 0.272 (R) | 1.000 | (1.456,0.831-2.549) | P = 0.189 (R) | 1.000 | (0.999,0.828-1.207) | P = 0.995 (F) | 1.000 |
 1 study | Turkish | 54/92 | (1.647,0.774-3.505) | P = 0.195 | 1.000 | (0.553,0.227-1.348) | P = 0.193 | 1.000 | (1.286,0.636-2.599) | P = 0.484 | 1.000 |
 2 studies | Indian | 301/352 | (0.542,0.284-1.034) | P = 0.063 (R) | 0.378 | (0.763,0.494-1.178) | P = 0.223 (F) | 1.000 | (0.555,0.272-1.130) | P = 0.105 (R) | 1.000 |
 1 study | Mexian | 45/123 | (0.929,0.373-2.316) | P = 0.875 | 1.000 | (0.295,0.084-.032) | P = 0.056 | 0.336 | (0.581,0.268-1.259) | P = 0.169 | 1.000 |
 1 study | Iranian | 50/100 | (0.520,0.226-1.197) | P = 0.124 | 0.744 | (1.770,0.824-3.803) | P = 0.143 | 0.858 | (0.697,0.325-1.495) | P = 0.354 | 1.000 |
IBS-C | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 20 studies | Overall | 992/2437 | (0.926,0.708-1.212) | P = 0.578 (R) | 1.000 | (1.545,1.187-2.012) | P = 0.001 (R) | 0.006 | (1.119,0.890-1.406) | P = 0.335 (R) | 1.000 |
 8 studies | Cau/M Cau | 462/841 | (1.266,0.883-1.815) | P = 0.199 (F) | 1.000 | (1.327,1.027-1.715) | P = 0.031 (F) | 0.186 | (1.398,0.994-1.968) | P = 0.054 (F) | 0.324 |
 8 studies | East Asian | 393/1052 | (0.906,0.672-1.220) | P = 0.514 (F) | 1.000 | (2.759,1.933-3.938) | P = 0.000 (F) | 0.000 | (1.250,0.964-1.622) | P = 0.093 (F) | 0.558 |
 1 study | Turkish | 26/92 | (0.882,0.337-2.307) | P = 0.799 | 1.000 | (0.579,0.180-1.860) | P = 0.358 | 1.000 | (0.750,0.312-1.803) | P = 0.165 | 0.990 |
 2 studies | Indian | 96/352 | (0.783,0.185-3.324) | P = 0.740 (R) | 1.000 | (0.726,0.378-1.394) | P = 0.336 (F) | 1.000 | (0.753,0.213-2.661) | P = 0.660 (R) | 1.000 |
 1 study | Iranian | 15/100 | (0.342,0.095-1.234) | P = 0.101 | 0.606 | (1.368,0.395-4.734) | P = 0.621 | 1.000 | (0.448,0.144-1.391) | P = 0.165 | 0.990 |
IBS-D | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 21 studies | Overall | 1454/2813 | (0.863,0.619-1.205) | P = 0.387 (R) | 1.000 | (1.042,0.862-1.260) | P = 0.668 (R) | 1.000 | (0.885,0.648-1.209) | P = 0.443 (R) | 1.000 |
 9 studies | Cau/M Cau | 806/1270 | (0.854,0.548-1.332) | P = 0.423 (R) | 1.000 | (1.113,0.914-1.357) | P = 0.286 (F) | 1.000 | (0.922,0.626-1.357) | P = 0.680 (R) | 1.000 |
 8 studies | East Asian | 434/999 | (0.896,0.686-1.171) | P = 0.423 (F) | 1.000 | (0.850,0.561-1.289) | P = 0.444 (F) | 1.000 | (0.843,0.656-1.083) | P = 0.181 (F) | 1.000 |
 1 study | Turkish | 18/92 | (8.471,1.811-39.626) | P = 0.007 | 0.042 | (0.085,0.005-1.462) | P = 0.089 | 0.534 | (5.143,1.115-23.714) | P = 0.036 | 0.096 |
 2 studies | Indian | 171/352 | (0.321,0.024-4.370) | P = 0.394 (R) | 1.000 | (0.680,0.214-2.159) | P = 0.513 (F) | 1.000 | (0.371,0.036-3.819) | P = 0.405 (R) | 1.000 |
 1 study | Iranian | 25/100 | (0.469,0.152-1.445) | P = 0.187 | 1.000 | (2.508,0.986-6.380) | P = 0.054 | 0.324 | (0.768,0.286-2.066) | P = 0.601 | 1.000 |
IBS-M | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 17 studies | Overall | 486/2042 | (0.920,0.706-1.199) | P = 0.538 (F) | 1.000 | (1.186,0.887-1.584) | P = 0.250 (R) | 1.000 | (0.971,0.760-1.242) | P = 0.817 (F) | 1.000 |
 6 studies | Cau/M Cau | 265/549 | (0.728,0.476-1.112) | P = 0.142 (F) | 0.852 | (1.172,0.707-1.942) | P = 0.539 (R) | 1.000 | (0.834,0.563-1.237) | P = 0.368 (F) | 1.000 |
 7 studies | East Asian | 167/949 | (1.106,0.750-1.632) | P = 0.611 (F) | 1.000 | (1.000,0.590-1.696) | P = 1.000 (F) | 1.000 | (1.082,0.754-1.554) | P = 0.669 (F) | 1.000 |
 1 study | Turkish | 10/92 | (6.353,0.727-55.545) | P = 0.095 | 0.570 | (1.364,0.325-5.726) | P = 0.672 | 1.000 | (5.786,0.703-47.626) | P = 0.103 | 0.618 |
 2 studies | Indian | 34/352 | (0.695,0.309-1.562) | P = 0.379 (F) | 1.000 | (1.421,0.611-3.303) | P = 0.415 (F) | 1.000 | (0.817,0.393-1.698) | P = 0.588 | 1.000 |
 1 study | Iranian | 10/100 | (1.232,0.231-6.560) | P = 0.807 | 1.000 | (0.940,0.186-4.764) | P = 0.941 | 1.000 | (1.195,0.237-6.025) | P = 0.829 | 1.000 |