Table 1 Breakdown of families with the most frequent BRCA1 mutations | Family | Mutation | Gene/exon | No of individuals | No of mutation carriers | No affected |
| 761 | 185delAG | BRCA1/2 | 4 | 1 | 0 |
| 2802 | 185delAG | BRCA1/2 | 26 | 11 | 3 |
| 5358 | 185delAG | BRCA1/2 | 2 | 1 | 1 |
| 9603 | 185delAG | BRCA1/2 | 1 | 1 | 0 |
| 9877 | 185delAG | BRCA1/2 | 4 | 4 | 1 |
| 12654 | 185delAG | BRCA1/2 | 1 | 1 | 1 |
| 13376 | 185delAG | BRCA1/2 | 2 | 1 | 1 |
| 17240 | 185delAG | BRCA1/2 | 2 | 2 | 2 |
| 17924 | 185delAG | BRCA1/2 | 2 | 1 | 1 |
| 21347 | 185delAG | BRCA1/2 | 2 | 2 | 2 |
| 27388 | 185delAG | BRCA1/2 | 4 | 2 | 1 |
| 30231 | 185delAG | BRCA1/2 | 2 | 1 | 1 |
| 2592 | 4184delTCAA | BRCA1/11 | 3 | 2 | 1 |
| 7836 | 4184delTCAA | BRCA1/11 | 4 | 3 | 1 |
| 9117 | 4184delTCAA | BRCA1/11 | 4 | 2 | 1 |
| 9430 | 4184delTCAA | BRCA1/11 | 3 | 2 | 2 |
| 10079 | 4184delTCAA | BRCA1/11 | 3 | 2 | 1 |
| 10502 | 4184delTCAA | BRCA1/11 | 2 | 1 | 1 |
| 11096 | 4184delTCAA | BRCA1/11 | 3 | 1 | 1 |
| 12779 | 4184delTCAA | BRCA1/11 | 3 | 1 | 1 |
| 14028 | 4184delTCAA | BRCA1/11 | 2 | 2 | 2 |
| 14562 | 4184delTCAA | BRCA1/11 | 3 | 2 | 1 |
| 16324 | 4184delTCAA | BRCA1/11 | 1 | 1 | 1 |
| 29694 | 4184delTCAA | BRCA1/11 | 7 | 4 | 3 |
| 32778 | 4184delTCAA | BRCA1/11 | 1 | 1 | 1 |
| 33164 | 4184delTCAA | BRCA1/11 | 1 | 1 | 1 |
| 39265 | 4184delTCAA | BRCA1/11 | 3 | 3 | 3 |
| 40426 | 4184delTCAA | BRCA1/11 | 1 | 1 | 0 |
| 3140 | Exon13 Dup | BRCA1/13 | 3 | 2 | 1 |
| 3429 | Exon13 Dup | BRCA1/13 | 2 | 2 | 1 |
| 9592 | Exon13 Dup | BRCA1/13 | 3 | 1 | 1 |
| 12157 | Exon13 Dup | BRCA1/13 | 1 | 1 | Unknown |
| 12468 | Exon13 Dup | BRCA1/13 | 2 | 2 | 1 |
| 20332 | Exon13 Dup | BRCA1/13 | 2 | 1 | 1 |
| 20597 | Exon13 Dup | BRCA1/13 | 1 | 1 | 1 |
| 21231 | Exon13 Dup | BRCA1/13 | 2 | 1 | 1 |
| 25940 | Exon13 Dup | BRCA1/13 | 2 | 2 | 1 |
| 27810 | Exon13 Dup | BRCA1/13 | 2 | 1 | 1 |
| 32563 | Exon13 Dup | BRCA1/13 | 2 | 2 | 2 |
| 36387 | Exon13 Dup | BRCA1/13 | 1 | 1 | 1 |
| 38199 | Exon13 Dup | BRCA1/13 | 2 | 1 | 1 |