Table 8.

MR results of the causal effect of ER-negative BC on MMP-7.

Exposure	Outcome	No. of SNPs	Method	β	P value	Heterogeneity		Pleiotropy
						Cochrane's Q	P	P
ER-negative BC (ieu-a-1128)	MMP7	37	MR Egger	− 0.08	0.20	21.49	0.96	0.29
			Weighted median	− 0.04	0.24
			Inverse variance weighted	− 0.02	0.38	22.63	0.96
			Simple mode	− 0.05	0.40
			Weighted mode	− 0.05	0.27
ER-negative BC (ieu-a-1135)	MMP7	14	MR Egger	− 0.12	0.17	3.49	0.99	0.29
			Weighted median	− 0.04	0.33
			Inverse variance weighted	− 0.03	0.24	4.73	0.98
			Simple mode	− 0.04	0.43
			Weighted mode	− 0.05	0.33
ER-negative BC (ieu-a-1136)	MMP7	7	MR Egger	0.07	0.63	2.03	0.84	0.60
			Weighted median	0.007	0.87
			Inverse variance weighted	− 0.004	0.90	2.34	0.89
			Simple mode	0.02	0.74
			Weighted mode	0.02	0.73
ER-negative BC (ieu-a-1166)	MMP7	8	MR Egger	0.14	0.55	2.07	0.91	0.50
			Weighted median	− 0.03	0.40
			Inverse variance weighted	− 0.01	0.65	2.58	0.92
			Simple mode	− 0.04	0.48
			Weighted mode	− 0.04	0.49

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