ADAM20

Summary

ADAM20 (ADAM metallopeptidase domain 20, HGNC:199) is a protein-coding gene on chromosome 14q24.2, encoding Disintegrin and metalloproteinase domain-containing protein 20 (O43506). May be involved in sperm maturation and/or fertilization.

This gene encodes a member of the ADAM (a disintegrin and metalloprotease domain) family. Members of this family are membrane-anchored proteins structurally related to snake venom disintegrins, and have been implicated in a variety of biological processes involving cell-cell and cell-matrix interactions, including fertilization, muscle development, and neurogenesis. The expression of this gene is testis-specific.

Source: NCBI Gene 8748 — RefSeq curated summary.

At a glance

• Gene–disease (curated): male infertility (Limited, GenCC)
• GWAS associations: 2
• Clinical variants (ClinVar): 128 total
• MANE Select transcript: NM_003814

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:199
Approved symbol	ADAM20
Name	ADAM metallopeptidase domain 20
Location	14q24.2
Locus type	gene with protein product
Status	Approved
Ensembl gene	ENSG00000134007
Ensembl biotype	protein_coding
OMIM	603712
Entrez	8748

Gene structure

Transcript identifiers

Ensembl transcripts: 2 — 2 protein_coding

ENST00000256389, ENST00000652041

RefSeq mRNA: 1 — MANE Select: NM_003814 NM_003814

CCDS: CCDS32111

Canonical transcript exons

ENST00000256389 — 2 exons

Exon	Start	End
ENSE00000911696	70522358	70524933
ENSE00003895539	70534797	70535004

Expression profiles

Bgee: expression breadth broad, 49 present calls, max score 90.68.

FANTOM5 (CAGE): breadth tissue_specific, TPM avg 0.0160 / max 13.0815, expressed in 3 samples.

FANTOM5 promoters (1 alternative TSS)

Promoter ID	TPM avg	Samples expressed
143918	0.0160	3

Top tissues by expression

210 total, by Bgee expression score (0-100, higher = more expressed):

Tissue	Anatomy ID	Expression score	Quality
sperm	CL:0000019	90.68	gold quality
male germ cell	CL:0000015	87.80	gold quality
primordial germ cell in gonad	CL:0000670 ∩ UBERON:0000991	84.97	gold quality
male germ line stem cell (sensu Vertebrata) in testis	CL:0000089 ∩ UBERON:0000473	80.30	gold quality
pancreatic ductal cell	CL:0002079	69.27	silver quality
ileal mucosa	UBERON:0000331	68.73	silver quality
right testis	UBERON:0004534	65.97	gold quality
left testis	UBERON:0004533	65.27	gold quality
testis	UBERON:0000473	64.79	gold quality
buccal mucosa cell	CL:0002336	64.74	silver quality
tibialis anterior	UBERON:0001385	61.98	silver quality
calcaneal tendon	UBERON:0003701	60.03	gold quality
oviduct epithelium	UBERON:0004804	59.81	gold quality
cervix epithelium	UBERON:0004801	58.11	gold quality
colonic epithelium	UBERON:0000397	57.00	silver quality
diaphragm	UBERON:0001103	56.39	gold quality
deltoid	UBERON:0001476	56.25	gold quality
myocardium	UBERON:0002349	55.19	gold quality
bone marrow cell	CL:0002092	54.96	gold quality
sural nerve	UBERON:0015488	53.80	gold quality
epithelium of nasopharynx	UBERON:0001951	53.25	gold quality
tendon	UBERON:0000043	53.00	gold quality
epithelial cell of pancreas	CL:0000083	52.80	gold quality
adult organism	UBERON:0007023	52.15	gold quality
corpus callosum	UBERON:0002336	51.55	gold quality
Brodmann (1909) area 46	UBERON:0006483	51.52	gold quality
muscle tissue	UBERON:0002385	51.34	gold quality
hindlimb stylopod muscle	UBERON:0004252	51.02	silver quality
uterine cervix	UBERON:0000002	51.00	silver quality
cortical plate	UBERON:0005343	50.83	gold quality

Single-cell (SCXA)

Detected in 1 experiment(s), a significant marker in 0.

Experiment	Marker?	Max mean expression
E-ANND-3	no	1.88

Regulation

Is transcription factor: no

miRNA regulators (miRDB)

17 targeting ADAM20, top 30 by miRDB confidence (max_score; target_count = how many genes the miRNA targets in total — lower means more specific):

miRNA	Max score	Avg score	miRNA target_count
HSA-MIR-3646	100.00	73.56	5283
HSA-MIR-3662	99.99	73.82	5684
HSA-MIR-4482-3P	99.98	72.50	3147
HSA-MIR-3912-5P	99.95	66.11	925
HSA-MIR-137-3P	99.87	74.74	2401
HSA-MIR-378A-5P	99.65	66.33	1311
HSA-MIR-561-3P	99.64	70.90	3647
HSA-MIR-142-5P	99.48	70.92	2416
HSA-MIR-5590-3P	99.48	70.91	2429
HSA-MIR-1261	98.62	68.10	896
HSA-MIR-4720-3P	98.50	68.88	988
HSA-MIR-1248	98.47	67.54	1314
HSA-MIR-3121-5P	97.30	66.62	1146
HSA-MIR-4327	97.21	67.71	676
HSA-MIR-3201	97.16	65.42	1044
HSA-MIR-4791	96.51	67.76	659
HSA-MIR-3914	94.91	65.77	643

Cross-species orthologs

9 orthologs

Organism	Symbol	Gene ID
danio_rerio	adam10b	ENSDARG00000015502
danio_rerio	adam10a	ENSDARG00000053468
danio_rerio	adam9b	ENSDARG00000057138
mus_musculus	Adam20	ENSMUSG00000046282
mus_musculus	Adam39	ENSMUSG00000054033
mus_musculus	Adam25	ENSMUSG00000071937
rattus_norvegicus	Adam25	ENSRNOG00000011397
drosophila_melanogaster	mmd	FBGN0259110
caenorhabditis_elegans		WBGENE00006804

Paralogs (20): ADAM22 (ENSG00000008277), ADAM28 (ENSG00000042980), ADAM7 (ENSG00000069206), ADAM11 (ENSG00000073670), ADAM2 (ENSG00000104755), ADAM23 (ENSG00000114948), ADAMDEC1 (ENSG00000134028), ADAM30 (ENSG00000134249), ADAM19 (ENSG00000135074), ADAM10 (ENSG00000137845), ADAM21 (ENSG00000139985), ADAM15 (ENSG00000143537), ADAM12 (ENSG00000148848), ADAM33 (ENSG00000149451), ADAM8 (ENSG00000151651), ADAM17 (ENSG00000151694), ADAM29 (ENSG00000168594), ADAM9 (ENSG00000168615), ADAM18 (ENSG00000168619), ADAM32 (ENSG00000197140)

Protein

Protein identifiers

Disintegrin and metalloproteinase domain-containing protein 20 — O43506 (reviewed: O43506)

All UniProt accessions (2): A0A494C0E3, O43506

UniProt curated annotations — full annotation on UniProt →

Function. May be involved in sperm maturation and/or fertilization.

Subcellular location. Membrane.

Tissue specificity. Testis specific.

Post-translational modifications. Has no obvious cleavage site for furin endopeptidase, suggesting that the proteolytic processing is regulated.

Cofactor. Binds 1 zinc ion per subunit.

Domain organisation. A tripeptide motif (VGE) within disintegrin-like domain could be involved in the binding to egg integrin receptor and thus could mediate sperm/egg binding. The cysteine-rich domain encodes putative cell-fusion peptides, which could be involved in sperm-egg fusion. The conserved cysteine present in the cysteine-switch motif binds the catalytic zinc ion, thus inhibiting the enzyme. The dissociation of the cysteine from the zinc ion upon the activation-peptide release activates the enzyme.

Miscellaneous. May be the functional equivalent of ADAM 1/fertilin alpha which is a pseudogene in human.

RefSeq proteins (1): NP_003805* (*=MANE)

Domains & families (InterPro)

ID	Name	Type
IPR001590	Peptidase_M12B	Domain
IPR001762	Disintegrin_dom	Domain
IPR002870	Peptidase_M12B_N	Domain
IPR006586	ADAM_Cys-rich	Domain
IPR018358	Disintegrin_CS	Conserved_site
IPR024079	MetalloPept_cat_dom_sf	Homologous_superfamily
IPR034027	Reprolysin_adamalysin	Domain
IPR036436	Disintegrin_dom_sf	Homologous_superfamily

Pfam: PF00200, PF01421, PF01562, PF08516

UniProt features (31 total): disulfide bond 7, glycosylation site 6, binding site 4, domain 3, sequence conflict 2, topological domain 2, signal peptide 1, propeptide 1, active site 1, chain 1, sequence variant 1, transmembrane region 1, short sequence motif 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

Model	pLDDT	Fraction very-high
AF-O43506-F1	83.06	0.50

Functional residue map

Curated UniProt residues grouped by drug-discovery relevance — catalytic, ligand-binding, modification, and mutation-validated positions. Source: UniProtKB sequence features.

Catalytic / active sites (1): 343

Ligand- & substrate-binding residues (4): 173 (in inhibited form); 342; 346; 352

Disulfide bonds (7): 317–394, 357–379, 359–364, 465–485, 635–646, 640–652, 654–663

Glycosylation sites (6): 191, 226, 378, 438, 479, 587

Function

Pathways and Gene Ontology

Reactome pathways

3 pathways

ID	Pathway
R-HSA-2534343	Interaction With Cumulus Cells And The Zona Pellucida
R-HSA-1187000	Fertilization
R-HSA-1474165	Reproduction

MSigDB gene sets: 93 (showing top): GOBP_SINGLE_FERTILIZATION, GOMF_METALLOPEPTIDASE_ACTIVITY, MORF_BRCA1, GOCC_CELL_SURFACE, MORF_RAD51L3, chr14q24, MODULE_379, GOBP_REPRODUCTIVE_SYSTEM_DEVELOPMENT, MORF_CTSB, MORF_IL4, MORF_PRKCA, GOBP_SEX_DIFFERENTIATION, GOBP_DEVELOPMENTAL_PROCESS_INVOLVED_IN_REPRODUCTION, KANG_IMMORTALIZED_BY_TERT_DN, GOBP_FERTILIZATION

GO Biological Process (3): proteolysis (GO:0006508), single fertilization (GO:0007338), male gonad development (GO:0008584)

GO Molecular Function (5): metalloendopeptidase activity (GO:0004222), metallopeptidase activity (GO:0008237), metal ion binding (GO:0046872), peptidase activity (GO:0008233), hydrolase activity (GO:0016787)

GO Cellular Component (4): plasma membrane (GO:0005886), external side of plasma membrane (GO:0009897), sperm head plasma membrane (GO:1990913), membrane (GO:0016020)

Reactome top-level categories

Rollup of top-2 pathways:

Category	Pathways
Fertilization	1
Reproduction	1

GO top-level categories

Rollup of top GO terms by namespace:

Category	Terms
protein metabolic process	1
fertilization	1
gonad development	1
development of primary male sexual characteristics	1
endopeptidase activity	1
metallopeptidase activity	1
peptidase activity	1
cation binding	1
hydrolase activity	1
catalytic activity, acting on a protein	1
catalytic activity	1
membrane	1
cell periphery	1
plasma membrane	1
cell surface	1
side of membrane	1
sperm head	1
sperm plasma membrane	1
plasma membrane region	1
cellular anatomical structure	1

Protein interactions and networks

STRING

402 interactions, top by confidence (×1000):

Protein A	Protein B	Partner UniProt	Score
ADAM20	ERV3-1	Q14264	490
ADAM20	ERVFRD-1	P60508	490
ADAM20	C3orf22	Q8N5N4	466
ADAM20	RNASE12	Q5GAN4	418
ADAM20	C12orf56	Q8IXR9	417
ADAM20	PKDREJ	Q9NTG1	404
ADAM20	GMCL1	Q96IK5	402
ADAM20	SMIM17	P0DL12	399
ADAM20	SH2D7	A6NKC9	391
ADAM20	ERVW-1	Q9UQF0	381
ADAM20	ANKRD62	A6NC57	379
ADAM20	CC2D2B	Q6DHV5	376
ADAM20	C1orf167	Q5SNV9	376
ADAM20	C22orf42	Q6IC83	375
ADAM20	SPDYE4	A6NLX3	369

IntAct

2 interactions, top by confidence:

A	B	Type	Score
Dlg4	ADAM20	psi-mi:“MI:0407”(direct interaction)	0.440

BioGRID (3): ADAM20 (Affinity Capture-RNA), ADAM30 (Negative Genetic), ADAM9 (Negative Genetic)

ESM2 similar proteins: O35674, O43184, O43506, O75173, O88839, O95450, P57110, P58459, P59384, P59511, P70505, P78325, P79331, P97857, Q05910, Q13443, Q13444, Q14114, Q1EHB3, Q4VC17, Q5RFQ8, Q60813, Q61072, Q61824, Q62179, Q64151, Q68SA9, Q69Z28, Q8BNJ2, Q8C9W3, Q8TE57, Q8TE58, Q8TE60, Q8WXS8, Q924X6, Q9ESP7, Q9H013, Q9H324, Q9JI76, Q9JLN6

Diamond homologs: A0A0B4U9L8, A3R0T9, A4PBQ9, A8QL48, A8QL49, A8QL59, B8K1W0, C5H5D1, C5H5D2, C5H5D3, C5H5D4, C5H5D5, C5H5D6, C9E1R7, C9E1R8, C9E1S0, D3TTC1, D3TTC2, D5LMJ3, D8VNS0, F8S108, G5EDW5, J3S829, J3S830, J3SDW6, J3SDW8, J9Z332, O35674, O42138, O43184, O43506, O75077, O77780, O88839, O93523, P0C6B6, P0C6E8, P0C7B0, P0DM87, P0DM89

SIGNOR signaling

0 interactions.

Disease & clinical

Clinical variants and AI predictions

ClinVar

128 variants total. Per-class counts are floors (≥ shown; pagination cap):

Classification	Count (floor)
Pathogenic	0
Likely pathogenic	0
Uncertain significance	115
Likely benign	11
Benign	0

Top pathogenic / likely-pathogenic (0)

SpliceAI

196 predictions. Top by Δscore:

Variant	Effect	Δscore
14:70533082:T:TC	acceptor_gain	0.9900
14:70533079:T:TC	acceptor_gain	0.9800
14:70533064:CAGT:C	acceptor_gain	0.9400
14:70533079:T:C	acceptor_gain	0.9400
14:70533082:T:C	acceptor_gain	0.9400
14:70534791:TCTTA:T	donor_loss	0.9000
14:70534792:CTTA:C	donor_loss	0.9000
14:70534793:TTACC:T	donor_loss	0.9000
14:70534794:TACCT:T	donor_loss	0.9000
14:70534795:ACCT:A	donor_loss	0.9000
14:70534796:C:CT	donor_loss	0.9000
14:70534790:ATCTT:A	donor_loss	0.8900
14:70534796:CCT:C	donor_gain	0.8800
14:70524013:C:G	acceptor_gain	0.8500
14:70533076:CAAT:C	acceptor_gain	0.8500
14:70524085:T:TG	acceptor_gain	0.8300
14:70533065:A:T	acceptor_gain	0.8300
14:70524084:C:CC	acceptor_gain	0.7900
14:70534328:C:CT	donor_gain	0.7900
14:70534329:T:TT	donor_gain	0.7900
14:70524083:A:AC	acceptor_gain	0.7800
14:70524935:T:A	acceptor_gain	0.7600
14:70524934:CTGAA:C	acceptor_gain	0.7500
14:70533067:T:C	acceptor_gain	0.7500
14:70533067:T:TC	acceptor_gain	0.7500
14:70524931:AAACT:A	acceptor_gain	0.7400
14:70524932:AACTG:A	acceptor_gain	0.7400
14:70524933:ACTGA:A	acceptor_gain	0.7400
14:70533077:A:T	acceptor_gain	0.7400
14:70534795:A:AC	donor_gain	0.7300

AlphaMissense

4850 scored. Top likely-pathogenic:

Variant	Protein change	am_pathogenicity
14:70523618:A:C	S380R	0.995
14:70523618:A:T	S380R	0.995
14:70523620:T:G	S380R	0.995
14:70523627:G:C	S377R	0.993
14:70523627:G:T	S377R	0.993
14:70523629:T:G	S377R	0.993
14:70523214:C:G	C515S	0.992
14:70523215:A:T	C515S	0.992
14:70523628:C:A	S377I	0.990
14:70524112:C:G	D216H	0.990
14:70523061:C:G	C566S	0.989
14:70523062:A:T	C566S	0.989
14:70523660:C:A	M366I	0.989
14:70523660:C:G	M366I	0.989
14:70523660:C:T	M366I	0.989
14:70524111:T:A	D216V	0.989
14:70523097:C:G	C554S	0.988
14:70523098:A:T	C554S	0.988
14:70523720:A:C	H346Q	0.988
14:70523720:A:T	H346Q	0.988
14:70523076:C:G	C561S	0.987
14:70523077:A:T	C561S	0.987
14:70523667:C:G	C364S	0.987
14:70523668:A:T	C364S	0.987
14:70523722:G:C	H346D	0.987
14:70522821:C:G	C646S	0.986
14:70522822:A:T	C646S	0.986
14:70523343:C:G	C472S	0.986
14:70523344:A:T	C472S	0.986
14:70523666:G:C	C364W	0.986

dbSNP variants (sampled 300 via entrez): RS1000009572 (14:70541789 C>T), RS1000053754 (14:70547291 G>T), RS1000129176 (14:70535623 C>T), RS1000179207 (14:70563161 A>C), RS1000184111 (14:70570399 C>A,T), RS1000513005 (14:70540028 C>T), RS1000534085 (14:70537655 C>A,T), RS1000613766 (14:70543408 C>T), RS1000710516 (14:70540193 T>G), RS1000719127 (14:70562884 T>A,C), RS1000740642 (14:70534214 T>A), RS1000751761 (14:70554621 G>T), RS1000789050 (14:70545708 T>C), RS1000910953 (14:70573671 C>T), RS1000954388 (14:70567662 G>A,C)

Disease associations

OMIM: gene MIM:603712 | disease phenotypes:

GenCC curated gene-disease

Disease	Classification	Inheritance
male infertility	Limited	Autosomal dominant

Mondo (1): male infertility (MONDO:0005372)

Orphanet (0):

HPO phenotypes

0 total (0 of 0 shown, HPO-id order):

GWAS associations

2 associations (top):

Study	Trait	p-value
GCST010245_12	LDL cholesterol levels	3.000000e-10
GCST012137_4	Motor coordination	2.000000e-06

EFO canonical traits (2, from GWAS)

EFO ID	Trait name
EFO:0004611	low density lipoprotein cholesterol measurement
EFO:0010749	motor function measurement

MeSH disease descriptors (1)

Descriptor	Name	Tree numbers
D007248	Infertility, Male	C12.100.500.430; C12.100.750.700; C12.200.294.430

Drugs & pharmacology

Drug and pharmacology data

Is drug target: no

PharmGKB: 1 entry (VIP=true, CPIC=false)

GtoPdb / IUPHAR curated pharmacology

(IUPHAR/BPS Guide to Pharmacology — expert-curated)

Target class: enzyme — M12: Astacin/Adamalysin

CTD chemical–gene interactions

10 total (human), top 10 by PubMed support.

Chemical	Actions (top 5)	PubMed papers
aristolochic acid I	increases expression	1
kojic acid	decreases expression	1
sodium arsenite	increases expression	1
potassium chromate(VI)	affects cotreatment, increases expression	1
epigallocatechin gallate	affects cotreatment, increases expression	1
CGP 52608	affects binding, increases reaction	1
Arbutin	decreases expression	1
Tobacco Smoke Pollution	increases expression	1
Aflatoxin B1	increases methylation	1
Lactic Acid	increases expression	1

Clinical trials (associated diseases)

125 trials via MONDO — disease-level, not drug-specific.

Trial	Phase	Status	Title
NCT02202382	PHASE4	COMPLETED	Effects of Korean Red Ginseng on Male Infertility
NCT02204826	PHASE4	COMPLETED	Effects of Korean Red Ginseng on Semen Parameters in Male Infertility Patients: a Randomized, Placebo-controlled, Double-blind Clinical Study
NCT03802864	PHASE4	COMPLETED	Post-operative Pain Control of Testicular Sperm Extraction Using Liposomal Bupivacaine
NCT06100432	PHASE4	ACTIVE_NOT_RECRUITING	Effect of Eurycoma Longifolia (DLBS5055) and Multivitamins (Vitamin C+Vitamin E+ β-carotene) for Infertile Males
NCT07523022	PHASE4	ENROLLING_BY_INVITATION	Comparison of the Effect of Gonadotropin and Clomiphene Citrate Treatment on Sperm Parameters and the Outcome of Assisted Reproductive Procedures in Subfertile Men Based on the APHRODITE Groups
NCT00975117	PHASE3	COMPLETED	Spermotrend in the Treatment of Male Infertility
NCT01407432	PHASE3	COMPLETED	Impact of Folates in the Care of the Male Infertility
NCT01895816	PHASE3	COMPLETED	Herbal Tonic Fertile Supplement(ZO2C5)
NCT02605070	PHASE3	TERMINATED	Pilot Study on the Effects of FSH Treatment on the Epigenetic Characteristics of Spermatozoa in Infertile Patients With Severe Oligozoospermia
NCT07402759	PHASE3	ACTIVE_NOT_RECRUITING	Impact of tdrd9 Gene Mutations in the Therapeutic Response to L-carnitine in Oligoasthenozoospermic Men
NCT01880086	PHASE2	COMPLETED	Clomiphene Citrate for the Treatment of Low Testosterone Associated With Chronic Opioid Pain Medication Administration
NCT02061384	PHASE2	COMPLETED	RA-2 13-cis Retinoic Acid (Isotretinoin)
NCT02421887	PHASE2	COMPLETED	Males, Antioxidants, and Infertility Trial
NCT05200663	PHASE2	UNKNOWN	Efficacy Comparison of Tamoxifen and Tamoxifen With Antioxidants on Semen Quality of Male With Idiopathic Infertility
NCT05290558	PHASE2	ACTIVE_NOT_RECRUITING	The Therapeutic Effects of Bu Shen Yi Jing Pill on Semen Quality in Sub Fertile Males: a Randomized Controlled Trial
NCT06091969	PHASE2	NOT_YET_RECRUITING	Supplementation for Male Subfertility
NCT01595308	PHASE1	COMPLETED	A Pilot Study to Evaluate the Effect of Pomegranate Juice on Semen Parameters in Healthy Male Volunteers
NCT02122211	PHASE1	COMPLETED	Choline Dehydrogenase and Sperm Function: Effects of Betaine
NCT02575924	PHASE1	UNKNOWN	Influence of Culture Media on Clinical Outcomes in Poor Responders or Severe Male Infertility
NCT01304927	PHASE2/PHASE3	COMPLETED	Vitamin D Supplementation and Male Infertility: The CBG-study a Randomized Clinical Trial
NCT02349945	PHASE2/PHASE3	COMPLETED	FSH Receptor Polymorphism p.N680S and Efficacy of FSH Therapy
NCT05222841	PHASE2/PHASE3	COMPLETED	The Effectiveness of Spermotrend Food Supplement in the Treatment of Male Infertility
NCT05616598	PHASE2/PHASE3	COMPLETED	Effect of New Oral Treatment for Hepatitis C Virus on Seminal Parameters
NCT02025270	PHASE1/PHASE2	COMPLETED	MSCs For Treatment of Azoospermic Patients
NCT04541459	EARLY_PHASE1	UNKNOWN	Validation of New Devices Against Ambient Electromagnetic Radiation
NCT05792813	EARLY_PHASE1	UNKNOWN	Efficacy and Safety of Linggui Yangyuan Paste in Patients With Male Infertility
NCT06188936	EARLY_PHASE1	COMPLETED	Home Semen Analysis Tests As a Screening Tool for Fertility Patients
NCT00012480	Not specified	COMPLETED	Effect of Environmental Exposures on the Egg Fertilizing Ability of Human Sperm
NCT00044369	Not specified	COMPLETED	Role of the Toxic Metal Cadmium in the Mechanism Producing Infertility With a Varicocele
NCT00119925	Not specified	UNKNOWN	‘SPRING’-Study: Subfertility Guidelines: Patient Related Implementation in the Netherlands Among Gynaecologists
NCT00178516	Not specified	COMPLETED	Vitamin E and Male Infertility
NCT00315029	Not specified	COMPLETED	Patient-Centered Implementation Trial for Single Embryo Transfer
NCT00341120	Not specified	COMPLETED	Genetic Causes of Male Infertility
NCT00481403	Not specified	COMPLETED	Study of Sperm Molecular Factors Implicated in Male Fertility
NCT00548977	Not specified	COMPLETED	Genetic Studies Spermatogenic Failure
NCT00596739	Not specified	COMPLETED	A Study of the Pre- and Post-operative Semen Analyses and Reproductive Hormone Levels of Men Undergoing Weight-reduction Surgery
NCT00756561	Not specified	COMPLETED	HOP-2A - Intratesticular Hormone Levels
NCT00961558	Not specified	TERMINATED	Canadian Varicocelectomy Initiative (CVI): Effects on Male Fertility and Testicular Function of Varicocelectomy
NCT01075334	Not specified	UNKNOWN	Is a Carnitine Based Food Supplement (PorimoreTM) for Infertile Men Superior to Folate and Zinc With Regard to Pregnancy Rates in Intrauterine Insemination Cycles?
NCT01178463	Not specified	UNKNOWN	Spermatogonial Stem Cells in Azoospermic Patients: a Comparison Between Obstructive and Non-obstructive Azoospermia