Table 3.

Frequency of Promoter Methylation by Case-Control Status^A, ^B

	RASSF1A	GSTP1	APC	RARβ2	At least One Gene MethylatedC
	Frequency % (n) 95% CI	Frequency % (n) 95% CI	Frequency % (n) 95% CI	Frequency % (n) 95% CI	Frequency % (n) 95% CI
Cases	22.0 (11/50)	4.0 (2/50)	2.0 (1/49)	6.7 (3/45)	31.8 (14/44)
	10.5, 33.5	−1.4, 9.4	−1.9, 5.9	−0.6, 14.0	18.0, 45.6
BBD	22.9 (11/48)	10.4 (5/48)	4.4 (2/46)	2.3 (1/43)	38.4 (15/39)
Controls	11.0, 34.8	1.8, 19.0	−1.5, 10.3	−2.2, 6.8	24.5, 52.3
Healthy	17.2 (17/99)	7.1 (7/99)	4.2 (4/96)	1.1 (1/88)	24.4 (21/86)
Controls	9.8, 24.6	2.0, 12.2	0.2, 8.2	−1.1, 3.3	15.3, 33.5

^AMethylation Frequencies (PMR>0) by case-control status, no statistical differences were found (Conditional logistic regression).

^B7 subjects were excluded due to undetectable ACTB levels in at least one of the assays (4 BBD controls and 3 healthy controls). In the case of RARβ2 additional samples did not amplify in the first round of analysis and were not repeated due to the precious nature of the samples and the results of the completed genes indicating that the frequency of methylation did not differ between cases and controls.

^CIncludes those women who had methylation measurements for all four genes