Figure 2.

Methylation analysis of four-gene panel in DL fluid from BRCA1 and BRCA2 carriers and controls. The genes in the panel were HIN-1, RAR-β, Twist and Cyclin D2. Ducts are identified as being from the left or right breast. Individual ducts are identified sequentially as a, b or c. The suffix 1 or 2 indicates the first or second lavage visit, respectively, for ducts from which repeat samples were taken 1 year apart. For example, left a2 indicates that a sample was taken from the left breast, duct a at the second ductal lavage (DL) visit. Black boxes indicate methylated genes, white boxes indicate unmethylated genes, and grey boxes indicate repeated failure of PCR reaction or inconclusive result. *Subject 11 had long-standing atypia identified in both breasts on nipple aspirate fluid cytology. **BRCA2 carriers affected by contralateral breast cancer. DL samples were collected from only their healthy unaffected breasts. ICMD, insufficient cellular material for diagnosis.