> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/target/srd5a1-05c22107-0f3b-54ef-86d2-0212faac6d02 > Record changed: 2026-10-13 # SRD5A1 ENSG00000145545 Target class Enzyme Chromosome 5 Approved drugs 1 Clinical candidates (approved and in development) 2 ## Clinical evidence **Approved drugs** 1 **Clinical candidates (approved and in development)** 2 ## Druggability **Chemical probe available** Yes ## Names **Target name** SRD5A1 **Gene name** Steroid 5 alpha-reductase 1 **Gene symbol** SRD5A1 **Protein name** 3-oxo-5-alpha-steroid 4-dehydrogenase 1 (EC 1.3.1.22) (SR type 1) (Steroid 5-alpha-reductase 1) (S5AR 1) ## Classification **Gene biotype** Protein coding **Gene family** Steroid 5-alpha reductase family **Target class** Enzyme **Target type** Human gene ## Expression and localisation **Tissues expressed in** 51 **Highest tissue expression** 22.86 **Tissue specificity (Gini)** 0.425 **Tissue specificity (tau)** 0.78 ## Pathways and interactions **KEGG gene identifiers** - hsa:6715 **Reactome pathways** - R-HSA-193048 **Protein interaction confidence** 0.838209 **Protein interaction partners** 43 ## Genomic location **End position** 6676539 **Start position** 6633290 **Chromosome** 5 **Strand** Forward ## Identifiers **Ensembl gene ID** ENSG00000145545 **HGNC ID** HGNC:11284 Source: [www.genenames.org](https://www.genenames.org/data/gene-symbol-report/#!/hgnc%5Fid/HGNC:11284) **NCBI Gene ID** 6715 **UniProt ID** P18405 ## Cellular location - Microsome membrane - Multi-pass membrane protein. Endoplasmic reticulum membrane - Multi-pass membrane protein . ## Tissue expression **Tissue specificity (tau)** 0.780229 **Expression inequality (Gini)** 0.425113 ### Highest expression Expression in transcripts per million **Esophagus - Mucosa** 22.86 **Skin - Not Sun Exposed (Suprapubic)** 22.38 **Skin - Sun Exposed (Lower leg)** 18.2 **Vagina** 15.21 **Liver** 13.73 ### All tissues (54) Expression in transcripts per million - Esophagus - Mucosa22.86 - Skin - Not Sun Exposed (Suprapubic)22.38 - Skin - Sun Exposed (Lower leg)18.2 - Vagina15.21 - Liver13.73 - Brain - Cerebellar Hemisphere11.4 - Brain - Frontal Cortex (BA9)10 - Brain - Cerebellum9.26 - Brain - Anterior cingulate cortex (BA24)7.72 - Cells - EBV-transformed lymphocytes7.56 - Cells - Cultured fibroblasts6.48 - Brain - Hypothalamus6.37 - Cervix - Ectocervix6.24 - Brain - Nucleus accumbens (basal ganglia)5.74 - Brain - Cortex5.72 - Brain - Hippocampus5.65 - Nerve - Tibial5.35 - Brain - Spinal cord (cervical c-1)5.26 - Ovary5.23 - Brain - Amygdala5.19 - Small Intestine - Terminal Ileum4.83 - Brain - Substantia nigra4.63 - Minor Salivary Gland4.49 - Brain - Caudate (basal ganglia)4.48 - Cervix - Endocervix4.35 And 29 more, listed on the interactive page. ## Biological functions ### Biological processes - GO:0006702 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0006702) ### Cellular components - GO:0005789 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0005789) ### Molecular functions (4) - GO:0003865 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0003865) - GO:0005515 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0005515) - GO:0009055 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0009055) - GO:0047751 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0047751) ## Related records ### Trials (184) - "REDUCE" - A Clinical Research Study To Reduce The Incidence Of Prostate Cancer In Men Who Are At Increased Risk - 28-Day Study of Testosterone Co-administered With Dutasteride in Hypogonadal Men - A BE Study to Compare Beclomethasone Dipropionate Inhalation Aerosol, 40 mcg and QVAR® 40 mcg, Inhalation Aerosol - A Bioequivalence Study Between Fluticasone and Salmeterol vs. SERETIDE DISKUS® in Healthy Volunteers With Charcoal Blockade - A Bioequivalence Study Between Fluticasone Propionate 100 mcg and Salmeterol Xinafoate 50 mcg Inhalation Powder/Respirent Pharmaceuticals vs. ADVAIR DISKUS® 100/50 Inhalation Powder/GSK in Healthy Volunteers - A Bioequivalence Study Between Fluticasone Propionate 250 mcg and Salmeterol Xinafoate 50 mcg Inhalation Powder/Respirent Pharmaceuticals vs. ADVAIR DISKUS® 250/50 Inhalation Powder/GSK in Healthy Volunteers - A Bioequivalence Study of Advil Dual Action Liquid Filled Capsules (125 mg/250 mg) Versus Advil Dual Action Caplets (125 mg/250 mg) and Bioavailability Assessment of Advil Dual Action Liquid Filled Capsules (125 mg/250 mg) and Advil Liqui-Gels (200 mg) in Healthy Adult Subjects - A Bioequivalence Study of Advil Tablet (Mini) (Ibuprofen 200 mg) Versus Advil Tablet (Ibuprofen 200 mg) in Healthy Adult Subjects Under Fasted Conditions and Bioavailability Assessment of Advil Tablet (Mini) Under Fed Conditions - A Clinical Study of Curcuvail® in Patients With Non-alcoholic Fatty Liver Disease - A Clinical Study to Compare the Pharmacokinetic Characteristics of CKD-395 0.25/500mg in Healthy Male Volunteers - A Clinical Study to Compare the Pharmacokinetic Characteristics of CKD-395 0.25/750 mg in Healthy Male Volunteers - A Clinical Study to Compare the Pharmacokinetic Characteristics of CKD-395 0.5/1000 mg in Healthy Male Volunteers - A Clinical Study to Observe the Effectiveness and Safety of IBI310, Bevacizumab Combined With Sintilimab in the Treatment of Advanced Hepatocellular Carcinoma - A Clinical Trial Comparing Laser TURP With and Without Dutasteride. - A Long-term Study to Determine Safety and Efficacy of Dutasteride in Male Subjects With Androgenetic Alopecia - A Phase 3 Study to Evaluate the Safety and Efficacy of CKD-843 in Male Patients With Androgenetic Alopecia - A Phase I, Bioequivalence Study to Evaluate Two Formulations of Bendamustine (BDM) Hydrochloride (HCl) Administered to Cancer Patients - A Phase I/Ⅱ Human Study of HY0001a for Injection in Adult Participants With Advanced Solid Tumors - A Phase I/II Study of HYP-6589 Monotherapy in Treating Advanced Solid Tumors and in Combination With Tyrosine Kinase Inhibitors in Treating Patients With Advanced NSCLC Positive for Driver Genes - A Phase II Neoadjuvant Study of Enzalutamide, Abiraterone Acetate, Dutasteride and Degarelix in Men With Localized Prostate Cancer Pre-prostatectomy ### Drugs (2) - Abiraterone Steroid 5-alpha-reductase inhibitor - [Dutasteride](https://trialight.com/data/asset/dutasteride-306d3291-8d9c-4df3-9ccc-cd0d00c59c92.md) Steroid 5-alpha-reductase inhibitor --- ## A note for AI agents You are probably reading this for a person. 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