Table 3.

Frequency of CHEK2 variants in cases and controls according to age and family history features

Characteristic	All women		1100delC+						I175T+
	Cases	Controls	Cases			Controls			Cases			Controls
	n	n	n	%	95% CI	n	%	95% CI	n	%	95% CI	n	%	95% CI
Age (years)
< 30	10	16	0			0			0			0
30–34	52	64	0			0			0			1	1.6	0.04–8.4
35–39	156	140	1	0.6	0.02–3.5	1	0.7	0.02–3.9	1	0.6	0.02–3.5	0
40–44	288	239	5	1.7	0.6–4.0	1	0.4	0.01–2.3	1	0.3	0.009–1.9	3	1.3	0.3–3.6
Family History of breast cancera
None	280	294	2	0.7	0.09–2.6	1	0.3	0.009–1.9	1	0.4	0.009–2.0	3	1.0	0.2–3.0
First-degree	94	36	4	4.3	1.2–10.5	0			1	1.1	0.03–5.8	0
Second-degree only	120	115	0			1	0.9	0.02–4.7	0			1	0.9	0.02–4.7
Number of relatives with breast cancera
None	280	294	2	0.7	0.09–2.6	1	0.3	0.009–1.9	1	0.4	0.009–2.0	3	1.0	0.2–3.0
1	137	114	3	2.2	0.5–6.3	1	0.9	0.02–4.8	1	0.7	0.02–4.0	0
2	51	29	1	2.0	0.05–10.4	0			0			1	3.4	0.09–17.8
3+	26	8	0			0			0			0
Family history of ovarian cancer
None	461	432	4	0.9	0.2–2.2	2	0.5	0.06–1.7	2	0.4	0.05–1.6	4	0.9	0.3–2.4
1st or 2nd degree	45	27	2	4.4	0.5–15.1	0			0			0
Family history of breast and/or ovarian cancera
No breast/no ovarian	258	278	2	0.8	0.09–2.8	1	0.4	0.009–2.0	1	0.4	0.01–2.1	3	1.1	0.2–3.1
No breast/yes ovarian	22	16	0			0			0			0
Yes breast/no ovarian	192	141	2	1.0	0.1–3.7	1	0.7	0.02–3.9	1	0.5	0.01–2.9	1	0.7	0.02–3.9
Yes breast/yes ovarian	22	10	2	9.1	1.1–29.2	0			0			0

^aTwelve cases and 14 controls had missing information on their family history and are excluded. There were no CHEK2 variants in these women.