| Exon no | Familial mutation | No of individuals (%) withBRCA1 mutations (n = 136) |
| 11 | 917_918delTT | 1 (1.7) |
| 887insAG* | 1 (1.7) | |
| 887insA* | 1 (1.7) | |
| 4184delTCAA | 29 (49.2)‡ | |
| 3896delT | 5 (8.5) | |
| 3889delAG | 3 (5.1) | |
| 3875delGTCT | 2 (3.4) | |
| 3519G>T (E1134X) | 1 (1.7) | |
| 3450_3453delCAAG | 1 (1.7) | |
| 2871A>C* | 1 (1.7) | |
| 2800delAA | 1 (1.7) | |
| 2682C>T (Q855X) | 1 (1.7) | |
| 2594delC | 2 (3.4) | |
| 2559insA* | 1 (1.7) | |
| 2196G>A (D693N) | 1 (1.7) | |
| 2080delA | 1 (1.7) | |
| 2011insT | 1 (1.7) | |
| 1927C>G* | 1 (1.7) | |
| 1623del5bp | 2 (3.4) | |
| 1294del40bp | 2 (3.4) | |
| Total | 58 | |
| 13 | Ex13ins6kb | 4 (20) |
| ex13 dup | 14 (70)§ | |
| 4446C>T (R1443X) | 2 (10) | |
| Total | 20 | |
| 15 | 4693delAA | 1 (50) |
| 4654G>T (S1512I) | 1 (50) | |
| Total | 2 | |
| 16 | 5075G>A (M1652I) | 1 (100) |
| Total | 1 | |
| 1A–2 | Exons 1A–2 deletion | 2 (100) |
| Total | 2 | |
| 2 | 187–188delAG* | 1 (3.3) |
| 185insA† | 1 (3.3) | |
| 185delAG | 28 (93.3)¶ | |
| Total | 30 | |
| 20 | ivs20+60 ins12bp | 1 (8.3) |
| Exon 20 deletion | 7 (58.3) | |
| 5382insC | 4 (33.3) | |
| Total | 12 | |
| 22 | 5452–2A>C* | 1 (100) |
| Total | 1 | |
| 24 | 5622C>T (R1835X) | 5 (100) |
| Total | 5 | |
| 3 | Exon 3 deletion | 3 (100) |
| Total | 3 | |
| 5 | 300T>C (C61R) | 1 (100) |
| Total | 1 | |
| 7 | 421–2delA | 1 (100) |
| Total | 1 |
*Novel mutations not reported in the Breast Cancer Information Core database.
†Reported in Pakistan.36
‡Number of families = 13.
§Number of families = 12.
¶Number of families = 11.