Figure 1. The estrogen metabolic pathway is depicted. The top and bottom sections represent the extracellular space, and the middle section represents the intracellular space. The mitochondrial compartment is labeled in pink. Enzymes are labeled in green and estrogen metabolites are labeled in grey. Protein definitions with corresponding abbreviations and their associated genes are as follows: CDR=Aldo-keto reductase family 1 member C4 (Chlordecone reductase), coded by AKR1C4; 3-oxo-5-beta-steroid 4-dehydrogenase=3-oxo-5-beta-steroid 4-dehydrogenase, coded by AKR1D1; ASD=Arylsulfatase D, coded by ARSD; COMT=catechol-O-methyltransferase, coded by COMT; CYP11A=cytochrome P450, family 11, subfamily A, polypeptide 1, coded by CYP11A1; CYP11B1=cytochrome P450, family 11, subfamily B, polypeptide 1, coded by CYP11B1; CYP17=cytochrome P450, family 17, subfamily A, polypeptide 1, coded by CYP17A1; CYP19A1=Cytochrome P450 19A1, coded by CYP19A1; CYP1A1=cytochrome P450, family 1, subfamily A, polypeptide 1, coded by CYP1A1; CYP1A2=cytochrome P450, family 1, subfamily A, polypeptide 2, coded by CYP1A2; CYP1B1=Cytochrome P450 1B1, coded by CYP1B1; CYP3A4=cytochrome P450, family 3, subfamily A, polypeptide 4, coded by CYP3A4; 11-beta-HSD1=Corticosteroid 11-beta-dehydrogenase isozyme 1 (11-beta-hydroxysteroid dehydrogenase 1), coded by HSD11B1; 17-beta-HSD1=Estradiol 17-beta-dehydrogenase 1 (17-beta-hydroxysteroid dehydrogenase type 1), coded by HSD17B1; 17-beta-HSD3=hydroxysteroid (17-beta) dehydrogenase 3, coded by HSD17B3; 3-beta-HSD1=3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 1, coded by HSD3B1; SRD5A1=steroid-5-alpha-reductase, alpha polypeptide 1 (3-oxo-5 alpha-steroid delta 4-dehydrogenase alpha 1), coded by SRD5A1; ASC=Steryl-sulfatase (Arylsulfatase C), coded by STS; EST-1=Estrogen sulfotransferase, coded by SULT1E1; SULT2B1=Sulfotransferase family cytosolic 2B member 1, coded by SULT2B1; UDPGT 2B11=UDP-glucuronosyltransferase 2B11, coded by UGT2B11. Two genes not in the figure but in the pathway analysis are ESR1=estrogen receptor 1, coded by ESR1; ESR2=estrogen receptor 2 (ER beta), coded by ESR2. Single nucleotide polymorphisms for these genes are derived from the Illumina platform array. Additional abbreviations for estrogen metabolites are as follows: OH=hydroxyl; Me=methoxy