Table 1.

Association between the PRS and breast cancer risk in case–control and breast cancer family datasets

Sample group		N	PRS	p value
			OR [95 % CI]
Case–control dataset	Healthy population controls	1269	Reference
	All BC cases	1689	1.56 [1.45–1.68]	9.2E−31
	Unselected breast cancer cases	1299	1.49 [1.38–1.62]	3.5E−23
	Sporadic breast cancer cases	1020	1.41 [1.30–1.54]	5.1E−16
	Index cases from small families	334	1.85 [1.63–2.11]	8.8E−21
	Index cases from large families	305	1.81 [1.59–2.06]	2.0E−19
52 breast cancer families	Affected family members	181	1.82 [1.55–2.13]	1.8E−13
	Affected family members with no affected first-degree relatives	50	1.62 [1.22–2.14]	7.7E−4
	Affected family members with one affected first-degree relative	58	1.97 [1.52–2.57]	4.0E−7
	Affected family members with two affected first-degree relatives	47	1.74 [1.30–2.33]	1.8E−4
	Affected family members with three or more affected first-degree relatives	26	2.05 [1.40–3.02]	2.5E−4
Healthy family members (52 breast cancer families) vs. healthy population controlsa		246 vs. 1269	1.29 [1.12–1.48]	3.4E−4

^aTest for association between PRS and positive family history of breast cancer comparing healthy women from the breast cancer families to healthy population controls