Table 10.

MR results of the causal effect of ER-negative BC on MMP-12.

Exposure	Outcome	No. of SNPs	Method	β	P value	Heterogeneity		Pleiotropy
						Cochrane's Q	P	P
ER-negative BC (ieu-a-1128)	MMP12	37	MR Egger	− 0.06	0.27	35.09	0.46	0.24
			Weighted median	0.02	0.50
			Inverse variance weighted	− 0.001	0.98	36.52	0.44
			Simple mode	0.06	0.39
			Weighted mode	0.04	0.46
ER-negative BC (ieu-a-1135)	MMP12	14	MR Egger	− 0.18	0.04	10.66	0.56	0.05
			Weighted median	0.02	0.61
			Inverse variance weighted	− 0.02	0.50	15.36	0.29
			Simple mode	0.04	0.54
			Weighted mode	0.05	0.54
ER-negative BC (ieu-a-1136)	MMP12	7	MR Egger	0.03	0.87	6.09	0.30	0.83
			Weighted median	0.01	0.82
			Inverse variance weighted	− 0.01	0.80	6.15	0.41
			Simple mode	0.04	0.55
			Weighted mode	0.04	0.62
ER-negative BC (ieu-a-1166)	MMP12	8	MR Egger	− 0.09	0.70	7.09	0.31	0.78
			Weighted median	− 0.02	0.62
			Inverse variance weighted	− 0.03	0.36	7.19	0.41
			Simple mode	0.03	0.71
			Weighted mode	0.02	0.73

BC Breast cancer; ER Estrogen receptor; MMP Matrix metalloproteinases; MR Mendelian randomization; SNP Single nucleotide polymorphisms.