Minimum Sample Sizes
Pg 190. Statistical Genomics: Linkage, Mapping, and
QTL Analysis.
Minimum sample sizes need to detect linkage using
a = 0.05 (for discrete classes
not marker -QTL classes).
| True
Q |
Power |
BC |
F
- CC |
F
- CD |
F
- DD |
F
- DDr |
| 0.05 |
0.80
0.95 |
16
26 |
11
19 |
21
34 |
21
35 |
97
160 |
| 0.10 |
0.80
0.95 |
21
35 |
16
27 |
28
47 |
30
49 |
108
179 |
| 0.20 |
0.80
0.95 |
41
67 |
35
58 |
57
95 |
63
105 |
156
259 |
| 0.30 |
0.80
0.95 |
95
158 |
88
146 |
139
230 |
166
275 |
297
491 |
BC - testcross
CC - both codominant markers
CD - one codominant and one dominant marker
DDc - both dominant markers in coupling linkage phase
DDr - both dominant markers in repulsion linkage phase
The table shows that codominant markers for F2 populations
require a smaller sample size than testcross progeny
for the same recombination value and power of the test.
F2 doubly dominant markers in coupling phase linkage
require a smaller sample size than when in repulsion
linkage for the same recombination value and power. As the recombination value increases in the same column, the sample size must be increased.
Conclusions:
The amount of information provided by a set of data depends on three
factors.
- The closeness of linkage
- The type of linkage, whether repulsion or coupling
- The type of family, whether testcross, F2 with dominance,
or completely classified F2 with progeny data.
