The number of cells to karyotype in order to exclude a minimum level of mosaicism at a specific confidence limit can be determined based on the following table.
Assumptions for use:
(1) The probability of mosaicism is constant and independent in the cells examined.
(2) The table is most appropriate for cells in the first metaphase division in vitro. In long term cultures a clone may outgrow or undergrow other cells.
(3) This does not include the influence of technical factors which may cause the gain or loss of a chromosome. More than the minimum number of cells may need to be analyzed in order to feel confident that the findings reflect the cytogenetics of the cell.
|
Minimum Level of Mosaicism Excluded |
||
---|---|---|---|
Cells Counted |
90% Confidence Limit |
95% Confidence Limit |
99% Confidence Limit |
5 |
38% |
|
|
6 |
32% |
41% |
|
7 |
29% |
35% |
|
8 |
26% |
32% |
46% |
9 |
23% |
29% |
41% |
10 |
21% |
26% |
37% |
11 |
19% |
24% |
35% |
12 |
18% |
23% |
32% |
13 |
17% |
21% |
30% |
14 |
16% |
20% |
29% |
15 |
15% |
19% |
27% |
16 |
14% |
18% |
26% |
17 |
13% |
17% |
24% |
18 |
13% |
16% |
23% |
19 |
12% |
15% |
22% |
20 |
11% |
14% |
21% |
21 |
11% |
14% |
20% |
22 |
10% |
13% |
19% |
23 |
10% |
13% |
19% |
24 |
10% |
12% |
18% |
25 |
9% |
12% |
17% |
26 |
9% |
11% |
17% |
27 |
9% |
11% |
16% |
28 |
8% |
11% |
16% |
29 |
8% |
10% |
15% |
30 |
8% |
10% |
15% |
31 |
8% |
10% |
14% |
32 |
7% |
9% |
14% |
33 |
7% |
9% |
14% |
34 |
7% |
9% |
13% |
35 |
7% |
9% |
13% |
36 |
7% |
8% |
13% |
37 |
7% |
8% |
12% |
38 |
6% |
8% |
12% |
39 |
6% |
8% |
12% |
40 |
6% |
8% |
11% |
41 |
6% |
8% |
11% |
42 |
6% |
7% |
11% |
43 |
6% |
7% |
11% |
44 |
6% |
7% |
10% |
45 |
5% |
7% |
10% |
46 |
5% |
7% |
10% |
47 |
5% |
7% |
10% |
48 |
5% |
7% |
10% |
49 |
5% |
6% |
9% |
50 - 55 |
5% |
6% |
9% |
56 |
5% |
6% |
8% |
57 - 58 |
4% |
6% |
8% |
59 - 63 |
4% |
5% |
8% |
64 - 73 |
4% |
5% |
7% |
74 |
4% |
4% |
7% |
75 |
4% |
4% |
6% |
76 – 89 |
3% |
4% |
6% |
90 – 98 |
3% |
4% |
5% |
99 – 112 |
3% |
3% |
5% |
113 |
3% |
3% |
4% |
114 – 148 |
2% |
3% |
4% |
149 – 151 |
2% |
2% |
4% |
152 – 227 |
2% |
2% |
3% |
228 – 229 |
2% |
2% |
2% |
230 – 298 |
1% |
2% |
2% |
299 – 458 |
1% |
1% |
2% |
>= 459 |
1% |
1% |
1% |
from Table I, page 95
Specialty: Genetics