TABLE 3.
TNF-α genotype distribution and genotype frequencies in the Gezira cohorta
| Poly- morphism | Geno- type | No. with genotype/no. genotyped (% with genotype)
|
P (Fisher's exact test)c | |
|---|---|---|---|---|
| Controlsb | Cases | |||
| TNF-α −376 | G/G | 321/344 (93.3) | 66/70 (94.3) | |
| G/A | 22/344 (6.4) | 3/70 (4.3) | 1 | |
| A/A | 1/344 (0.3) | 1/70 (1.4) | ||
| TNF-α −308 | G/G | 275/342 (80.4) | 58/70 (82.9) | |
| G/A | 63/342 (18.4) | 12/70 (7.1) | 0.636 | |
| A/A | 4/342 (1.2) | 0/70 (0) | ||
| TNF-α −238 | G/G | 288/341 (84.5) | 58/70 (82.9) | |
| G/A | 52/341 (15.2) | 11/70 (15.7) | 0.738 | |
| A/A | 1/341 (0.3) | 1/70 (1.4) | ||
A case-control study was performed with patients recruited at the endoscopy unit of Wad Medani Teaching Hospital (Sudan). Healthy controls were recruited from contributors to the Wad Medani blood bank or from nearby villages. All patients with evidence of PPF and varices attending the hospital during the study period were included. Thus, the inclusion criteria were PPF diagnosed by ultrasound and esophageal varices diagnosed by endoscopy. The patients gave informed consent for participation in the study. Control subjects were matched with the patients (cases) for age and sex. All controls lived in the area of the Gezira region in which S. mansoni is endemic.
The genotype distributions for the three polymorphisms did not deviate from Hardy-Weinberg equilibrium within the control group (χ2 = 1.05, 0.03, and 0.71 for TNF-α −376, −308, and −238, respectively).
Fisher's exact test was carried out with SPSS software to test the association between TNF-α polymorphisms and disease.