Table 4.

Lack of detectable peripheral blood BRCA1 methylation in family members of women in this study

Individual IDPeripheral blood methylation (%) of the probandRelationship to the probandCancer status (age of diagnosis)Peripheral blood methylation
Relatives of probands with detectable peripheral blood methylationa
Group 1
 P1.1>5SisterNot affectedNot methylated
 P1.2>5SisterNot affectedNot methylated
SisterNot affectedNot methylated
 P1.51–5Paternal auntBreast (69)Not methylated
 P1.61–5Maternal auntOvary (65)Not methylated
 P1.71SisterBreast (37); Overlapping lesion of the breast (51)Not methylated
 P1.81MotherBreast (45)Not methylated
 P1.131–5FatherNot affectedNot methylated
MotherTongue (46); Breast (51)Not methylated
Maternal uncleNot affectedNot methylated
SisterNot affectedNot methylated
BrotherNot affectedNot methylated
 P1.14>5MotherNot affectedNot methylated
Group 3
 P3.83.5–5FatherNot affectedNot methylated
Other relatives with breast or ovarian cancer b
Group 1
 P1.9Not methylatedMotherBreast (47)Not methylated
Group 3
 P3.2Not methylatedMotherBreast (68)Not methylated
 P3.3Not methylatedMotherBreast (74)Not methylated
Paternal auntBreast (76)Not methylated
 P3.4Not methylatedMotherBreast (72)Not methylated
 P2.5Not methylatedMotherOvary (68)Not methylated

NOTE: Figures in parentheses indicate the age of onset of the tumors.

  • aPeripheral blood BRCA1 promoter methylation in family members of women with moderate levels of peripheral blood BRCA1 promoter methylation.

  • bBRCA1 promoter methylation in peripheral blood DNA of affected family members (breast and/or ovarian cancer) of group 1 and group 3 women without peripheral blood methylation.