Common genetic variation in IGF1, IGFBP-1, and IGFBP-3 in relation to mammographic density: a cross-sectional study

Table 4 Mean percentage mammographic density (MD) according to insulin-like growth factor haplotype-tagging SNPs

SNP	Genotype	n	Mean percentage MD^a	p for trend^b
1	C/C	2	19.1	0.13
	C/T	71	29.5
	T/T	1,035	26.5
2	A/A	20	29.1	0.07
	A/G	308	25.0
	G/G	748	27.4
3	A/A	51	27.3	0.74
	A/G	388	26.6
	G/G	662	26.5
4	A/A	23	25.9	0.89
	A/C	284	26.7
	C/C	816	26.8
5	G/G	47	24.7	0.74
	C/G	403	26.6
	C/C	657	26.8
6	G/G	88	24.3	0.05
	A/G	419	26.4
	A/A	569	27.6
7	A/A	7	20.1	0.007
	A/G	155	24.7
	G/G	934	27.4
8	T/T	20	29.3	0.18
	G/T	255	27.9
	G/G	776	26.4
9	G/G	36	19.6	<0.0001
	C/G	325	24.8
	C/C	730	27.9
10	G/G	19	25.3	0.83
	G/C	262	27.4
	C/C	809	26.6
11	A/A	117	23.2	0.0004
	G/A	469	26.4
	G/G	503	28.2
12	C/C	59	24.3	0.16
	C/G	425	26.5
	G/G	605	27.2
13	G/G	270	27.0	0.60
	A/G	570	26.6
	A/A	278	26.8
14	G/G	26	26.1	0.82
	A/G	320	26.3
	A/A	750	26.9

^aMultivariate-adjusted models including age (continuous), body mass index (continuous), alcohol consumption (category), age at first birth/parity, history of benign breast disease (yes/no), family history of breast cancer (yes/no), menopausal status/postmenopausal hormone use (premenopausal, postmenopausal never user, postmenopausal current user, postmenopausal past user); ^b p for trend based on inclusion of genotype as an ordinal variable in models with square-root-transformed mammographic density as the dependent variable. Results in bold are significant (p ≤ 0.05).

ISSN: 1465-542X