Table 2.
Frequencies of the C9orf72 Pathological G4C2 Expansion in the European and Flanders-Belgian Cohorts
| FTLD | FTLD–ALS | Total | ||||
|---|---|---|---|---|---|---|
| European cohort | ||||||
| Total | 50/781 | 6.40% | 23/64 | 35.94% | 73/845 | 8.64% |
| Familial | 21/251 | 8.37% | 11/23 | 47.83% | 32/274 | 11.68% |
| Sporadic | 13/358 | 3.63% | 5/27 | 18.52% | 18/385 | 4.68% |
| Othera | 16/172 | 9.30% | 7/14 | 50.00% | 23/186 | 12.37% |
| Flanders-Belgian cohort | ||||||
| Total | 21/337 | 6.23% | 7/23 | 30.43% | 28/360 | 7.78% |
| Familial | 12/101 | 11.88% | 6/7 | 85.71% | 18/108 | 16.67% |
| Sporadic | 9/236 | 3.81% | 1/16 | 6.25% | 10/252 | 3.97% |
| Combined European and Flanders-Belgian cohorts | ||||||
| Total | 71/1118 | 6.35% | 30/87 | 34.48% | 101/1205 | 8.38% |
| Familial | 33/352 | 9.38% | 17/30 | 56.67% | 50/382 | 13.09% |
| Sporadic | 22/594 | 3.70% | 6/43 | 13.95% | 28/637 | 4.40% |
| Othera | 16/172 | 9.30% | 7/14 | 50.00% | 23/186 | 12.37% |
a
Other includes patients of which there was no family history data available in the European cohort.