| Zygosity | Pairs (n) | Prevalence, n (%) | Discordant pairs (n) | Concordant pairs (n) | CPr |
| Denmark | |||||
| MZ | 11085 | 41 (0.185) | 37 | 2 | 0.098 |
| DZ | 39391 | 129 (0.164) | 127 | 1 | 0.016 |
| Finland | |||||
| MZ | 3519 | 13 (0.185) | 9 | 2 | 0.038 |
| DZ | 7667 | 32 (0.209) | 32 | 0 | 0 |
| All MZ | 14604 | 54 (0.185) | 46 | 4 | 0.148 |
| All DZ | 47058 | 161 (0.171) | 159 | 1 | 0.012 |
| Total | 61662 | 215 (0.174) | 205 | 5 | 0.030 |
CPr, probandwise concordance rate.