Table 12.
(8) Observed and the optimal predicted concordance rates and prevalence rates for MS under different conditions.
| Observed (Estimated)* | 100% Recessive | 80% Recessive | 100% Dominant | 100% Mixed | |
|---|---|---|---|---|---|
| Number Genes Needed (n) | - | 14 | 13 | 58 | 58 |
| Frequency of Susceptibility (r) | - | 2 | 4 | 2 | 2 |
| Total Non-HLA Genes (x) | - | 58 - 61 | 100 - 107 | 246-254 | 246 - 254 |
| Relationship | |||||
| Prevalence [2,19] | 0.1 - 0.2% (1.5) | 0.14 - 0.21% | 0.12 - 0.21% | 0.00% | 0.00% |
| Non-twin Sibling [5,6] | 2.9 - 3.8% (3.0) | 3.7 - 4.3% | 3.3 - 4.1%. | 4.6 - 5.4% | 4.5 - 5.3% |
| Offspring, Conjugal MS** | ~10% (10.0) | 11.9 - 12.1% | 10.3 - 10.8% | 13.4% | 13.2 - 13.3% |
| Parent/Child [5] | 1.8 - 2.1% (2.0) | 1.8 - 2.3% | 1.3 - 1.8% | 4.6 - 5.4% | 4.3 - 5.1% |
| Second Degree [5] | 0.9 - 1.6% (1.0) | 0.8 - 1.1% | 0.7 - 1.1% | 0.1% | 0.1% |
| Third Degree [5] | 0.9% (0.9) | 0.3 - 0.5% | 0.3 - 0.5% | 0.00% | 0.00% |
| Closeness of Fit | - | 1.8 | 1.7 | 22.7 | 20.6 |
* The estimates (Targets) used to calculate closeness of fit are shown in parentheses. Closeness of fit was measured as the sum of the squared percent deviations of both the high and the low prediction from the Target. The optimal estimate was taken as the estimate at the values of x, n, and r that gave the closest fit to the observations.
** The concordance rate for the offspring of Conjugal MS is based on the report of Sadovnick et al. [6], in which the recurrence rate in offspring of two parents with MS is reported to be 78% of the monozygotic twin rate (CRMZ).