Table 2.
The MTHFR and TYMS genotype distributions, relative fitnesses and deviations from HWE of the genotypes in the 5 populations from Norfolk and Cumbria
| MTHFR | CC | CT | TT |
Relative fitness CC vs CT |
Relative fitness TT vs CT |
Deviation from HWE | |
|---|---|---|---|---|---|---|---|
| Cohort 1 | Observed | 486.0 | 564.0 | 128.0 | 0.92 | 0.85 | 0.063 |
| Expected | 500.7 | 534.6 | 142.7 | ||||
| Cohort 2 | Observed | 206.0 | 191.0 | 41.0 | 0.98 | 0.95 | 0.824 |
| Expected | 207.5 | 187.9 | 42.5 | ||||
| Cohort 3 | Observed | 179.0 | 178.0 | 52.0 | 1.06 | 1.11 | 0.445 |
| Expected | 175.6 | 184.8 | 48.6 | ||||
| Cohort 4 | Observed | 166.0 | 202.0 | 30.0 | 0.81 | 0.61 | 0.003 |
| Expected | 179.1 | 175.8 | 43.1 | ||||
| Cohort 5 | Observed | 185.0 | 214.0 | 76.0 | 1.08 | 1.13 | 0.287 |
| Expected | 179.5 | 225.0 | 70.5 | ||||
| TYMS | 3_3 | 2_3 | 2_2 |
Relative fitness 3_3 vs 3_2 |
Relative fitness 2_2 vs 3_2 |
Deviation from HWE | |
| Cohort 1 | Observed | 350.0 | 541.0 | 287.0 | 1.16 | 1.18 | 0.007 |
| Expected | 326.8 | 587.3 | 263.8 | ||||
| Cohort 2 | Observed | 126.0 | 216.0 | 96.0 | 1.02 | 1.01 | 0.848 |
| Expected | 125.0 | 218.0 | 95.0 | ||||
| Cohort 3 | Observed | 129.0 | 180.0 | 100.0 | 1.24 | 1.28 | 0.022 |
| Expected | 117.3 | 203.5 | 88.3 | ||||
| Cohort 4 | Observed | 124.0 | 184.0 | 90.0 | 1.14 | 1.16 | 0.189 |
| Expected | 117.2 | 197.6 | 83.2 | ||||
| Cohort 5 | Observed | 146.0 | 240.0 | 89.0 | 0.96 | 0.94 | 0.641 |
| Expected | 149.0 | 234.1 | 92.0 | ||||
Observed and expected genotype frequencies and deviations from HWE were calculated from the prevalence data for the MTHFR 677 and TYMS 5'UTR loci in 2898 samples that were simultaneously genotyped at both loci