Table 2

Phenotypic features of the BRCA1 methylated tumors

Tumour number

AI at BRCA1

AI at BRCA2

TP53 mutation

ER status

PR status

BRCA1 protein expression^a

DNA index

Interpretation of FISH

1

+

-

-

+

+

1

NA

Deletion of the BRCA1 region

2

+

-

-

-

-

1

1.68

Deletion of the BRCA1 region

3

+

+

+

-

-

1

1.12; 1.99

Chromosome 17 deletion

4

+

+

+

-

-

1

1.54

Chromosome 17 deletion

5

+

+

+

+

+

1

1.22; 2.18

Chromosome 17 deletion

6

-

-

-

+

+

1

NA

Chromosome 17 deletion

7

+

-

+

-

-

1

3.32

No detectable BRCA1 deletion

8

-

-

-

+

+

1

1.11; 1.80

No detectable BRCA1 deletion

9

+

+

+

-

-

1

1.00

No detectable BRCA1 deletion

10

-

-

-

+

+

2

1.69

No detectable BRCA1 deletion

11

-

-

-

-

-

3

1.00

No detectable BRCA1 deletion

12

-

-

-

+

+

3

2.09

No detectable BRCA1 deletion

13

+

+

-

-

NA

3

NA

No detectable BRCA1 deletion

^aBRCA1 protein expression in class 1 represents markedly reduced or absent expression; expression levels in class 2 and class 3 represent reduced and wild-type expression, respectively. AI, allelic imbalance; ER, estrogen receptor; NA, not available; PR, progesterone receptor.

Birgisdottir et al. Breast Cancer Research 2006 8:R38   doi:10.1186/bcr1522