For the apparently healthy child of a patient with Huntington's disease, it is important to estimate the risk of being affected. This can be done based on knowing the age of the child and the data from population studies.
Life-table analysis for first degree relatives from south Wales
|
Age |
Risk in Percent |
|
20.0 |
49.6% |
|
22.5 |
49.3% |
|
25.0 |
49.0% |
|
27.5 |
48.4% |
|
30.0 |
47.6% |
|
32.5 |
46.6% |
|
35.0 |
45.5% |
|
37.5 |
44.2% |
|
40.0 |
42.5% |
|
42.5 |
40.3% |
|
45.0 |
37.8% |
|
47.5 |
34.8% |
|
50.0 |
31.5% |
|
52.5 |
27.8% |
|
55.0 |
24.8% |
|
57.5 |
22.1% |
|
60.0 |
18.7% |
|
62.6 |
15.2% |
|
65.0 |
12.8% |
|
67.5 |
10.8% |
|
70.0 |
6.2% |
|
72.5 |
4.6% |
Second degree polynomials describing the data:
risk for ages 20 to 40 =
= (-0.000155 * ((age in years)^2)) + (0.0058195 * (age in years)) + 0.4413463
risk for ages 40 to 60 =
= (-0.000077 * ((age in years)^2)) - (0.004464 * (age in years)) + 0.7309221
risk for ages 60 to 72.5 =
= (0.0001716 * ((age in years)^2)) - (0.034305 * (age in years)) + 1.6283243
Specialty: Genetics, Neurology
