| HGNC Family | Defensins |
| Name | defensin, alpha 1B |
| Description | Defensins are a family of antimicrobial and cytotoxic peptides thought to be involved in host defense. They are abundant in the granules of neutrophils and also found in the epithelia of mucosal surfaces such as those of the intestine, respiratory tract, urinary tract, and vagina. Members of the defensin family are highly similar in protein sequence and distinguished by a conserved cysteine motif. The protein encoded by this gene, defensin, alpha 1, is found in the microbicidal granules of neutrophils and likely plays a role in phagocyte-mediated host defense. Several alpha defensin genes are clustered on chromosome 8. This gene differs from defensin, alpha 3 by only one amino acid. This gene and the gene encoding defensin, alpha 3 are both subject to copy number variation. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2014] |
| Summary |
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| Synonyms | HNP-1 |
| NCBI Gene ID | 728358 |
| API | |
| Download Associations | |
| Predicted Functions |
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| Co-expressed Genes |
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| Expression in Tissues and Cell Lines |
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DEFA1B has 1,237 functional associations with biological entities spanning 6 categories (molecular profile, functional term, phrase or reference, disease, phenotype or trait, chemical, cell line, cell type or tissue, gene, protein or microRNA) extracted from 39 datasets.
Click the + buttons to view associations for DEFA1B from the datasets below.
If available, associations are ranked by standardized value
| Dataset | Summary | |
|---|---|---|
| Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles | tissue samples with high or low expression of DEFA1B gene relative to other tissue samples from the Allen Brain Atlas Aging Dementia and Traumatic Brain Injury Tissue Sample Gene Expression Profiles dataset. | |
| CCLE Cell Line Gene CNV Profiles | cell lines with high or low copy number of DEFA1B gene relative to other cell lines from the CCLE Cell Line Gene CNV Profiles dataset. | |
| ChEA Transcription Factor Binding Site Profiles | transcription factor binding site profiles with transcription factor binding evidence at the promoter of DEFA1B gene from the CHEA Transcription Factor Binding Site Profiles dataset. | |
| ChEA Transcription Factor Targets | transcription factors binding the promoter of DEFA1B gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets dataset. | |
| ChEA Transcription Factor Targets 2022 | transcription factors binding the promoter of DEFA1B gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets 2022 dataset. | |
| COMPARTMENTS Curated Protein Localization Evidence Scores | cellular components containing DEFA1B protein from the COMPARTMENTS Curated Protein Localization Evidence Scores dataset. | |
| COMPARTMENTS Curated Protein Localization Evidence Scores 2025 | cellular components containing DEFA1B protein from the COMPARTMENTS Curated Protein Localization Evidence Scores 2025 dataset. | |
| COMPARTMENTS Text-mining Protein Localization Evidence Scores | cellular components co-occuring with DEFA1B protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores dataset. | |
| COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025 | cellular components co-occuring with DEFA1B protein in abstracts of biomedical publications from the COMPARTMENTS Text-mining Protein Localization Evidence Scores 2025 dataset. | |
| COSMIC Cell Line Gene CNV Profiles | cell lines with high or low copy number of DEFA1B gene relative to other cell lines from the COSMIC Cell Line Gene CNV Profiles dataset. | |
| DISEASES Experimental Gene-Disease Association Evidence Scores | diseases associated with DEFA1B gene in GWAS datasets from the DISEASES Experimental Gene-Disease Assocation Evidence Scores dataset. | |
| DISEASES Experimental Gene-Disease Association Evidence Scores 2025 | diseases associated with DEFA1B gene in GWAS datasets from the DISEASES Experimental Gene-Disease Assocation Evidence Scores 2025 dataset. | |
| DISEASES Text-mining Gene-Disease Association Evidence Scores | diseases co-occuring with DEFA1B gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores dataset. | |
| DISEASES Text-mining Gene-Disease Association Evidence Scores 2025 | diseases co-occuring with DEFA1B gene in abstracts of biomedical publications from the DISEASES Text-mining Gene-Disease Assocation Evidence Scores 2025 dataset. | |
| DisGeNET Gene-Disease Associations | diseases associated with DEFA1B gene in GWAS and other genetic association datasets from the DisGeNET Gene-Disease Associations dataset. | |
| DisGeNET Gene-Phenotype Associations | phenotypes associated with DEFA1B gene in GWAS and other genetic association datasets from the DisGeNET Gene-Phenoptype Associations dataset. | |
| ENCODE Transcription Factor Binding Site Profiles | transcription factor binding site profiles with transcription factor binding evidence at the promoter of DEFA1B gene from the ENCODE Transcription Factor Binding Site Profiles dataset. | |
| ENCODE Transcription Factor Targets | transcription factors binding the promoter of DEFA1B gene in ChIP-seq datasets from the ENCODE Transcription Factor Targets dataset. | |
| GeneRIF Biological Term Annotations | biological terms co-occuring with DEFA1B gene in literature-supported statements describing functions of genes from the GeneRIF Biological Term Annotations dataset. | |
| GeneSigDB Published Gene Signatures | PubMedIDs of publications reporting gene signatures containing DEFA1B from the GeneSigDB Published Gene Signatures dataset. | |
| GEO Signatures of Differentially Expressed Genes for Small Molecules | small molecule perturbations changing expression of DEFA1B gene from the GEO Signatures of Differentially Expressed Genes for Small Molecules dataset. | |
| GTEx Tissue Gene Expression Profiles | tissues with high or low expression of DEFA1B gene relative to other tissues from the GTEx Tissue Gene Expression Profiles dataset. | |
| GTEx Tissue Gene Expression Profiles 2023 | tissues with high or low expression of DEFA1B gene relative to other tissues from the GTEx Tissue Gene Expression Profiles 2023 dataset. | |
| GWAS Catalog SNP-Phenotype Associations 2025 | phenotypes associated with DEFA1B gene in GWAS datasets from the GWAS Catalog SNP-Phenotype Associations 2025 dataset. | |
| HPA Tissue Gene Expression Profiles | tissues with high or low expression of DEFA1B gene relative to other tissues from the HPA Tissue Gene Expression Profiles dataset. | |
| HPA Tissue Protein Expression Profiles | tissues with high or low expression of DEFA1B protein relative to other tissues from the HPA Tissue Protein Expression Profiles dataset. | |
| HPA Tissue Sample Gene Expression Profiles | tissue samples with high or low expression of DEFA1B gene relative to other tissue samples from the HPA Tissue Sample Gene Expression Profiles dataset. | |
| JASPAR Predicted Human Transcription Factor Targets 2025 | transcription factors regulating expression of DEFA1B gene predicted using known transcription factor binding site motifs from the JASPAR Predicted Human Transcription Factor Targets dataset. | |
| JASPAR Predicted Transcription Factor Targets | transcription factors regulating expression of DEFA1B gene predicted using known transcription factor binding site motifs from the JASPAR Predicted Transcription Factor Targets dataset. | |
| KEGG Pathways 2026 | pathways involving DEFA1B protein from the KEGG Pathways 2026 dataset. | |
| Klijn et al., Nat. Biotechnol., 2015 Cell Line Gene CNV Profiles | cell lines with high or low copy number of DEFA1B gene relative to other cell lines from the Klijn et al., Nat. Biotechnol., 2015 Cell Line Gene CNV Profiles dataset. | |
| RummaGEO Drug Perturbation Signatures | drug perturbations changing expression of DEFA1B gene from the RummaGEO Drug Perturbation Signatures dataset. | |
| TargetScan Predicted Nonconserved microRNA Targets | microRNAs regulating expression of DEFA1B gene predicted using nonconserved miRNA seed sequences from the TargetScan Predicted Nonconserved microRNA Targets dataset. | |
| TCGA Signatures of Differentially Expressed Genes for Tumors | tissue samples with high or low expression of DEFA1B gene relative to other tissue samples from the TCGA Signatures of Differentially Expressed Genes for Tumors dataset. | |
| TISSUES Curated Tissue Protein Expression Evidence Scores | tissues with high expression of DEFA1B protein from the TISSUES Curated Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Curated Tissue Protein Expression Evidence Scores 2025 | tissues with high expression of DEFA1B protein from the TISSUES Curated Tissue Protein Expression Evidence Scores 2025 dataset. | |
| TISSUES Experimental Tissue Protein Expression Evidence Scores | tissues with high expression of DEFA1B protein in proteomics datasets from the TISSUES Experimental Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Text-mining Tissue Protein Expression Evidence Scores | tissues co-occuring with DEFA1B protein in abstracts of biomedical publications from the TISSUES Text-mining Tissue Protein Expression Evidence Scores dataset. | |
| TISSUES Text-mining Tissue Protein Expression Evidence Scores 2025 | tissues co-occuring with DEFA1B protein in abstracts of biomedical publications from the TISSUES Text-mining Tissue Protein Expression Evidence Scores 2025 dataset. | |
