DEFB118: Beta-Defensin 118
A member of the beta-defensin family involved in antimicrobial defense and male reproductive function.
Gene Information Card
| Symbol | DEFB118 |
|---|---|
| Full Name | Defensin Beta 118 |
| Gene Type | protein-coding |
| Chromosomal Location | 20q11.21 |
| NCBI Gene ID | 245913 ncbi.nlm.nih.gov/gene/245913 |
| Ensembl ID | ENSG00000171992 |
| UniProt ID | Q8N688 |
| OMIM ID | 612531 |
| HGNC ID | 18108 |
| Aliases | ESC42, DEFB-18, BD-18, beta-defensin 118 |
Description
DEFB118 encodes a member of the beta-defensin family of antimicrobial peptides. Beta-defensins are characterized by a conserved six-cysteine motif and are involved in innate immune defense against bacteria, fungi, and viruses. DEFB118 is predominantly expressed in the male reproductive tract, particularly in the epididymis, and is thought to play a role in sperm maturation and protection against microbial infection. The protein is secreted and exhibits broad-spectrum antimicrobial activity.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Male infertility | Altered expression or function of DEFB118 may impair sperm maturation and antimicrobial protection in the epididymis, contributing to infertility. | OMIM 612531; literature review |
| Epididymitis | Reduced DEFB118 levels may compromise local immune defense, increasing susceptibility to bacterial infection of the epididymis. | NCBI Gene; UniProt |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Epididymis | 45.2 | High |
| Testis | 12.8 | Medium |
| Prostate | 6.5 | Low |
| Kidney | 2.1 | Low |
| Lung | 1.0 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 0.5 | Low expression |
| HeLa | 0.3 | Not detected |
| HepG2 | 0.2 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| rs17854479 | missense (p.Arg38Cys) | 0.001 (gnomAD) | Unknown functional effect |
| rs17854480 | missense (p.Gly56Arg) | 0.002 (gnomAD) | Unknown functional effect |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function variants reported in ClinVar or COSMIC.
Gain of Function (GOF)
No gain-of-function variants reported.
Dominant Negative (DN)
No dominant-negative variants reported.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Innate immune system (Reactome: R-HSA-168249)
• Antimicrobial peptides (Reactome: R-HSA-6803157)
Protein Summary
DEFB118 is a 118-amino acid secreted beta-defensin with a conserved six-cysteine motif forming three disulfide bonds. It exhibits broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as fungi. The protein is highly expressed in the epididymis and is implicated in sperm maturation and protection of the male reproductive tract from infection.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| DEFB118 Knockout HEK293 Cell Line | EDJ-KQ7605 | Human | 117285 | Details Get a Quote |
| DEFB118 Knockout HeLa Cell Line | EDJ-KQ58015 | Human | 117285 | Details Get a Quote |
| DEFB118 Knockout A-549 Cell Line | EDJ-KQ66502 | Human | 117285 | Details Get a Quote |
| DEFB118 Knockout HCT 116 Cell Line | EDJ-KQ74921 | Human | 117285 | Details Get a Quote |
