SRD5A2

Steroid-5-alpha-reductase, alpha polypeptide 2 (3-oxo-5 alpha-steroid delta 4-dehydrogenase alpha 2)
Identifiers
Symbols	SRD5A2; MGC138457
External IDs	OMIM: 607306 MGI: 2150380 HomoloGene: 37292 GeneCards: SRD5A2 Gene
EC number	1.3.99.5
Gene Ontology Molecular function • 3-oxo-5-alpha-steroid 4-dehydrogenase activity • sterol 5-alpha reductase activity Cellular component • cytoplasm • endoplasmic reticulum • endoplasmic reticulum membrane • microsome • membrane • integral to membrane Biological process • androgen biosynthetic process • cell-cell signaling • sex differentiation • steroid metabolic process • androgen metabolic process • male gonad development • cell differentiation • hormone biosynthetic process Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	6716	94224
Ensembl	ENSG00000049319	ENSMUSG00000038541
UniProt	P31213	Q3UTZ9
RefSeq (mRNA)	NM_000348.3	NM_053188.2
RefSeq (protein)	NP_000339.2	NP_444418.1
Location (UCSC)	Chr 2: 31.6 – 31.66 Mb	Chr 17: 74.37 – 74.4 Mb
PubMed search	[1]	[2]

3-oxo-5-alpha-steroid 4-dehydrogenase 2 is an enzyme that in humans is encoded by the SRD5A2 gene.

Steroid 5-alpha reductase catalyzes the conversion of the male sex hormone testosterone into the more potent androgen, dihydrotestosterone.

This gene encodes a microsomal protein expressed at high levels in androgen-sensitive tissues such as the prostate. The encoded protein is active at acidic pH and is sensitive to the 4-azasteroid inhibitor finasteride. Deficiencies in this gene can result in male pseudohermaphroditism, specifically pseudovaginal perineoscrotal hypospadias (PPSH).

See also

• 5-alpha reductase

Further reading

• Thigpen AE, Davis DL, Gautier T, et al. (1992). "Brief report: the molecular basis of steroid 5 alpha-reductase deficiency in a large Dominican kindred.". N. Engl. J. Med. 327 (17): 1216–9. doi:10.1056/NEJM199210223271706. PMID 1406794. 
• Labrie F, Sugimoto Y, Luu-The V, et al. (1992). "Structure of human type II 5 alpha-reductase gene.". Endocrinology 131 (3): 1571–3. doi:10.1210/en.131.3.1571. PMID 1505484. 
• Andersson S, Berman DM, Jenkins EP, Russell DW (1991). "Deletion of steroid 5 alpha-reductase 2 gene in male pseudohermaphroditism.". Nature 354 (6349): 159–61. doi:10.1038/354159a0. PMID 1944596. 
• Boudon C, Lobaccaro JM, Lumbroso S, et al. (1995). "A new deletion of the 5 alpha-reductase type 2 gene in a Turkish family with 5 alpha-reductase deficiency.". Clin. Endocrinol. (Oxf) 43 (2): 183–8. doi:10.1111/j.1365-2265.1995.tb01913.x. PMID 7554313. 
• Thigpen AE, Silver RI, Guileyardo JM, et al. (1993). "Tissue distribution and ontogeny of steroid 5 alpha-reductase isozyme expression.". J. Clin. Invest. 92 (2): 903–10. doi:10.1172/JCI116665. PMC 294929. PMID 7688765. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=294929. 
• Cai LQ, Zhu YS, Katz MD, et al. (1996). "5 alpha-reductase-2 gene mutations in the Dominican Republic.". J. Clin. Endocrinol. Metab. 81 (5): 1730–5. doi:10.1210/jc.81.5.1730. PMID 8626825. 
• Hochberg Z, Chayen R, Reiss N, et al. (1996). "Clinical, biochemical, and genetic findings in a large pedigree of male and female patients with 5 alpha-reductase 2 deficiency.". J. Clin. Endocrinol. Metab. 81 (8): 2821–7. doi:10.1210/jc.81.8.2821. PMID 8768837. 
• Vilchis F, Canto P, Chávez B, et al. (1997). "Molecular analysis of the 5 alpha-steroid reductase type 2 gene in a family with deficiency of the enzyme.". Am. J. Med. Genet. 69 (1): 69–72. doi:10.1002/(SICI)1096-8628(19970303)69:1<69::AID-AJMG13>3.0.CO;2-M. PMID 9066886. 
• Anwar R, Gilbey SG, New JP, Markham AF (1997). "Male pseudohermaphroditism resulting from a novel mutation in the human steroid 5 alpha-reductase type 2 gene (SRD5A2).". MP, Mol. Pathol. 50 (1): 51–2. doi:10.1136/mp.50.1.51. PMC 379579. PMID 9208814. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=379579. 
• Can S, Zhu YS, Cai LQ, et al. (1998). "The identification of 5 alpha-reductase-2 and 17 beta-hydroxysteroid dehydrogenase-3 gene defects in male pseudohermaphrodites from a Turkish kindred.". J. Clin. Endocrinol. Metab. 83 (2): 560–9. doi:10.1210/jc.83.2.560. PMID 9467575. 
• Nordenskjöld A, Ivarsson SA (1998). "Molecular characterization of 5 alpha-reductase type 2 deficiency and fertility in a Swedish family.". J. Clin. Endocrinol. Metab. 83 (9): 3236–8. doi:10.1210/jc.83.9.3236. PMID 9745434. 
• Nordenskjöld A, Magnus O, Aagenaes O, Knudtzon J (1999). "Homozygous mutation (A228T) in the 5alpha-reductase type 2 gene in a boy with 5alpha-reductase deficiency: genotype-phenotype correlations.". Am. J. Med. Genet. 80 (3): 269–72. doi:10.1002/(SICI)1096-8628(19981116)80:3<269::AID-AJMG18>3.0.CO;2-T. PMID 9843052. 
• Nnane IP, Kato K, Liu Y, et al. (1999). "Inhibition of androgen synthesis in human testicular and prostatic microsomes and in male rats by novel steroidal compounds.". Endocrinology 140 (6): 2891–7. doi:10.1210/en.140.6.2891. PMID 10342882. 
• Makridakis NM, Ross RK, Pike MC, et al. (1999). "Association of mis-sense substitution in SRD5A2 gene with prostate cancer in African-American and Hispanic men in Los Angeles, USA.". Lancet 354 (9183): 975–8. doi:10.1016/S0140-6736(98)11282-5. PMID 10501358. 
• Vilchis F, Méndez JP, Canto P, et al. (2000). "Identification of missense mutations in the SRD5A2 gene from patients with steroid 5alpha-reductase 2 deficiency.". Clin. Endocrinol. (Oxf) 52 (3): 383–7. doi:10.1046/j.1365-2265.2000.00941.x. PMID 10718838. 
• Hellwinkel OJ, Müller A, Struve D, Hiort O (2000). "Influence of androgens and age on androgen receptor and 5 alpha-reductase II transcription.". Eur. J. Endocrinol. 143 (2): 217–25. doi:10.1530/eje.0.1430217. PMID 10913941. 
• Chávez B, Valdez E, Vilchis F (2000). "Uniparental disomy in steroid 5alpha-reductase 2 deficiency.". J. Clin. Endocrinol. Metab. 85 (9): 3147–50. doi:10.1210/jc.85.9.3147. PMID 10999800. 
• Kim KS, Liu W, Cunha GR, et al. (2002). "Expression of the androgen receptor and 5 alpha-reductase type 2 in the developing human fetal penis and urethra.". Cell Tissue Res. 307 (2): 145–53. doi:10.1007/s004410100464. PMID 11845321. 
• Hiort O, Schütt SM, Bals-Pratsch M, et al. (2002). "A novel homozygous disruptive mutation in the SRD5A2-gene in a partially virilized patient with 5alpha-reductase deficiency.". Int. J. Androl. 25 (1): 55–8. doi:10.1046/j.1365-2605.2002.00325.x. PMID 11869378. 

This article incorporates text from the United States National Library of Medicine, which is in the public domain.