Table 1. The distribution of the val158met COMT polymorphism in patients with IBS compared to a sample representative of the general population.
| met/met | val/met | val/val | |
| IBS women+men (n = 70) | 31% | 39% | 30%* |
| Controls women+men (n = 867) | 31% | 49% | 20% |
| IBS women (n = 61) | 36% | 38% | 26% |
| Controls women (n = 445) | 32% | 48% | 20% |
| IBS men (n = 9) | 0% | 44% | 56% |
| Controls men (n = 422) | 30% | 51% | 19% |
There was a higher occurrence of the val/val genotype in patients compared with controls (30% vs 20%; Chi2 (1) 3.98; p = 0.046) and a trend toward a lower occurrence of the val/met genotype in IBS patients compared with controls (39% vs 49%; Chi2 (1) 2.89; p = 0.089).
*Statistically significant; p<0.05.