Table 2.
Sample size required to detect genetic associations combining different family structures for low penetrances*
| ε = 0 | ε = 0.005 | ε = 0.01 | |
|---|---|---|---|
| Dominant | |||
| p = 0.05 | 532(533) | 1702(1701) | ∞**(∞) |
| p = 0.20 | 355(357) | 456(457) | 2751(2969) |
| p = 0.70 | 4286(4306) | ∞ (∞) | ∞ (∞) |
| Recessive | |||
| p = 0.05 | 59117(59092) | ∞ (∞) | ∞ (∞) |
| p = 0.20 | 1494(1495) | 45486(∞) | ∞ (∞) |
| p = 0.70 | 270(270) | 353(353) | 3312(4511) |
| Multiplic. | |||
| p = 0.05 | 2026(2030) | ∞ (∞) | ∞ (∞) |
| p = 0.20 | 653(654) | 1135(1135) | ∞ (∞) |
| p = 0.70 | 639(640) | 1256(1255) | ∞ (∞) |
| Additive | |||
| p = 0.05 | 1209(1212) | ∞ (∞) | ∞ (∞) |
| p = 0.20 | 524(525) | 788(789) | 97207(∞) |
| p = 0.70 | 984(986) | 3547(3571) | ∞ (∞) |
*
The values in brackets are based on the weighting scheme suggested by Risch & Teng (1998);
**
∞ means that 80% power cannot be attained or the sample size required is unrealistically large (greater than 100 000); Significance level α = 5 × 10−8; power 1 − β = 0.80; Dominant model: f2 = f1 = 0.004, f0 = 0.001; Recessive model: f2 = 0.004, f1 = f0 = 0.001; Multiplicative model: f2 = 0.004, f1 = 0.002, f0 = 0.001; Additive model: f2 = 0.004, f1 = 0.0025, f0 = 0.001.