# IGLV1-44 Gene: Structure, Function, and Clinical Significance


## Key Takeaways

- The IGLV1-44 gene encodes a variable domain of the immunoglobulin lambda light chain, crucial for antigen binding via its three complementarity-determining regions (CDRs). Its V(D)J recombination and somatic hypermutation processes contribute to antibody diversity and affinity maturation, but aberrant mutations are implicated in B-cell malignancies like CLL and multiple myeloma.
- IGLV1-44 plays a significant role in autoimmune diseases, notably rheumatoid arthritis and systemic lupus erythematosus, where antibodies utilizing this gene can target self-antigens such as citrullinated proteins and dsDNA. Germline polymorphisms, like the K45E variant, are associated with increased CLL risk and differential response to therapies like rituximab.
- The gene is a critical biomarker for minimal residual disease (MRD) monitoring in B-cell malignancies, detectable through highly sensitive methods such as allele-specific oligonucleotide PCR (ASO-PCR) and next-generation sequencing (NGS), enabling precise quantification of clonal burden.
- Viral pathogens like EBV and HIV interact with IGLV1-44-expressing B cells; EBV's LMP2A mimics BCR signaling, promoting B-cell survival, while HIV gp120 can bind to IGLV1-44 CDR3, influencing antibody neutralization and therapeutic strategies for HIV.
- While not a direct drug target, IGLV1-44 is indirectly targeted by B-cell depleting therapies such as rituximab and daratumumab, and by CAR-T cell therapies (e.g., anti-CD19, anti-BCMA) used in treating B-cell malignancies. Small molecules like ibrutinib and venetoclax modulate BCR signaling pathways critical for these malignant cells.

---

## Executive Summary & Key Metadata

The **IGLV1-44** gene (Immunoglobulin Lambda Variable 1-44) encodes a variable domain of the immunoglobulin lambda light chain, a fundamental component of the adaptive immune system. This gene is a member of the immunoglobulin lambda variable (IGLV) gene family located on chromosome 22q11.2. The protein product, when rearranged with a lambda joining (IGLJ) segment and constant (IGLC) region, forms the light chain of antibodies that recognize and neutralize antigens. Beyond its canonical role in humoral immunity, IGLV1-44 has emerged as a clinically significant locus due to its involvement in B-cell malignancies, autoimmune disorders, and its utility as a biomarker for minimal residual disease (MRD) monitoring.

| **Metadata Field** | **Value** |
|---|---|
| HGNC Symbol | IGLV1-44 |
| UniProt Accession | P01699 |
| Representative PDB ID | true (multiple structures available, e.g., 6JOD, 5IMM) |
| Chromosomal Locus | 22q11.2 |
| Primary Molecular Function | Antigen binding; immunoglobulin lambda light chain variable domain |
| Disease & Pathology Associations | B-cell chronic lymphocytic leukemia (B-CLL), multiple myeloma, autoimmune diseases, viral infections |
| Gene Type | Protein-coding (immunoglobulin gene, rearranging) |
| Expression Pattern | B lymphocytes (pre-B, immature, mature, plasma cells) |

The IGLV1-44 gene product is a 112-amino-acid variable domain that folds into a characteristic immunoglobulin beta-sandwich structure. This domain contains three complementarity-determining regions (CDRs) that confer antigen specificity. The gene undergoes V(D)J recombination, somatic hypermutation (SHM), and class switch recombination (CSR) during B-cell development, making it a dynamic locus with significant genomic plasticity.

---

## 1. Genomic Locus, Chromosomal Organization & Isoforms

### 1.1 Chromosomal Location and Gene Structure

The IGLV1-44 gene is located on the **long arm of chromosome 22** at band **q11.2** (chr22:22,380,000–22,390,000; GRCh38/hg38). This region contains the entire immunoglobulin lambda light chain locus, which spans approximately 1.0 Mb and comprises:

- **~70 variable (V) genes** (of which ~30 are functional)
- **7 joining (J) segments**
- **7 constant (C) region genes** (IGLC1–IGLC7)

The IGLV1-44 gene is positioned in the **proximal cluster** of the lambda variable region, approximately 200 kb upstream of the J-C cluster. The gene spans **~1.2 kb** from the promoter to the recombination signal sequence (RSS) and contains:

- **Exon 1 (leader sequence):** Encodes a 15-amino-acid signal peptide that directs the nascent polypeptide into the endoplasmic reticulum.
- **Intron 1:** ~300 bp intervening sequence.
- **Exon 2 (variable domain):** Encodes the 112-amino-acid mature variable region, including framework regions (FR1–FR4) and CDRs.

The gene is flanked by a **5' promoter region** containing a TATA box and octamer motif (ATTTGCAT), which is recognized by the B-cell-specific transcription factor OCT-2 (POU2F2) and the ubiquitous factor OCT-1 (POU2F1). A **3' recombination signal sequence (RSS)** consisting of a heptamer (CACAGTG), a 23-bp spacer, and a nonamer (ACAAAAACC) directs V-J recombination.

### 1.2 Promoter Architecture and Enhancer Elements

The IGLV1-44 promoter is a **class III RNA polymerase II promoter** with the following architecture:

| **Element** | **Position (relative to TSS)** | **Binding Factor** | **Function** |
|---|---|---|---|
| TATA box | -30 to -25 | TFIID | Initiates transcription |
| Octamer motif | -70 to -63 | OCT-1/OCT-2 | B-cell-specific activation |
| E-box | -120 to -115 | E2A (TCF3) | Chromatin remodeling |
| κY element | -150 to -140 | NF-κB | Enhances transcription in activated B cells |

The **lambda enhancer (Eλ)** is located downstream of the IGLC genes and contains binding sites for **PU.1**, **IRF4**, and **E2A**. This enhancer is essential for high-level transcription in plasma cells. Additionally, a **3' enhancer (3'Eλ)** located 40 kb downstream of IGLC1 has been shown to regulate class switch recombination and somatic hypermutation.

### 1.3 V(D)J Recombination and Isoform Diversity

The IGLV1-44 gene does not produce multiple splice isoforms in the conventional sense. Instead, its diversity arises from **V(D)J recombination**:

1. **Rearrangement:** The IGLV1-44 gene rearranges with one of the 7 IGLJ segments and one of the 7 IGLC segments.
2. **Junctional diversity:** Exonucleolytic trimming and terminal deoxynucleotidyl transferase (TdT)-mediated N-nucleotide addition at the V-J junction generate CDR3 diversity.
3. **Somatic hypermutation:** Activation-induced cytidine deaminase (AID) introduces point mutations in the rearranged V gene at a rate of ~10⁻³ per base pair per cell division, leading to affinity maturation.

The resulting protein isoforms differ in their CDR3 sequences, which range from 5 to 13 amino acids in length. The most common rearrangement partners for IGLV1-44 are **IGLJ2** and **IGLC2**, producing the λ2 light chain isotype.

### 1.4 Epigenetic Regulation

The IGLV1-44 locus is subject to **allelic exclusion**—only one allele undergoes productive rearrangement in a given B cell. This is achieved through:

- **DNA methylation:** The promoter is hypermethylated in non-B cells and hypomethylated in B-cell precursors.
- **Histone modifications:** H3K4me3 marks the promoter in pro-B cells, while H3K9me2/3 represses it in non-lymphoid tissues.
- **Chromatin looping:** The 3' enhancer physically interacts with the promoter in a developmentally regulated manner, bringing the locus into the transcriptionally active compartment.

---

## 2. 3D Protein Domain Architecture & Structural Biology

### 2.1 Overall Fold

The IGLV1-44 protein domain (UniProt P01699) adopts the canonical **immunoglobulin fold**—a sandwich of two antiparallel β-sheets. The domain comprises **112 amino acids** organized into:

- **β-strands A, B, E, D** forming one sheet (4-stranded)
- **β-strands C, F, G** forming the opposing sheet (3-stranded)
- **Disulfide bond** between Cys23 (strand B) and Cys88 (strand F), stabilizing the fold

The structure is divided into **framework regions (FR1–FR4)** and **complementarity-determining regions (CDR1–CDR3)**:

| **Region** | **Residues** | **Structural Role** |
|---|---|---|
| FR1 | 1–23 | β-strands A and B |
| CDR1 | 24–34 | Loop between strands B and C |
| FR2 | 35–49 | β-strands C and C' |
| CDR2 | 50–56 | Loop between strands C' and D |
| FR3 | 57–88 | β-strands D, E, F |
| CDR3 | 89–97 | Loop between strands F and G |
| FR4 | 98–112 | β-strand G |

### 2.2 CDR Conformations and Antigen Binding

The three CDRs form the **antigen-binding site** at the N-terminal tip of the domain. Their canonical structures are:

- **CDR1 (L1):** 11 residues, adopts a Type 4 canonical conformation with a characteristic kink at position 29 (Ser).
- **CDR2 (L2):** 7 residues, Type 1 canonical conformation, forms a short hairpin.
- **CDR3 (L3):** 9–11 residues, Type 1 canonical conformation, contributes ~50% of the antigen contact surface.

The CDR loops are supported by a **conserved hydrophobic core** comprising residues Leu4, Val29, Ile48, Val58, Leu78, and Val98. This core maintains the structural integrity of the domain while allowing loop flexibility for antigen accommodation.

### 2.3 Post-Translational Modifications

The IGLV1-44 domain undergoes several post-translational modifications:

- **N-linked glycosylation:** A conserved N-glycosylation site at Asn70 (N-X-S/T motif) in FR3. This modification affects antigen binding affinity and serum half-life.
- **C-terminal processing:** The variable domain is synthesized as part of a precursor that includes the constant domain. Proteolytic cleavage at the V-C junction occurs during antibody assembly.
- **Disulfide bond formation:** The intradomain disulfide bond (Cys23–Cys88) forms co-translationally in the endoplasmic reticulum.

### 2.4 Structural Comparison with Other IGLV Genes

IGLV1-44 shares **85–90% sequence identity** with other IGLV1 family members (IGLV1-40, IGLV1-47, IGLV1-51). The major structural differences lie in:

- **CDR1 length:** IGLV1-44 has an 11-residue CDR1, whereas IGLV1-51 has a 12-residue CDR1.
- **CDR3 charge:** IGLV1-44 CDR3 is typically neutral or slightly acidic, while IGLV1-40 CDR3 is basic.
- **Framework packing:** A Val→Ile substitution at position 58 in IGLV1-44 alters the hydrophobic core packing, affecting thermal stability.

### 2.5 Interactive 3D Visualization

[Interactive 3D Protein Visualizer: Load IGLV1-44 (PDB: true)](/tools/protein-structure-viewer?source=alphafold&accession=P01699)

The interactive visualizer allows users to:

- Rotate and zoom the 3D structure
- Color by secondary structure, hydrophobicity, or conservation
- Highlight CDR loops and framework regions
- Overlay mutation data from ClinVar
- Measure atomic distances between antigen contact residues

---

## 3. Cellular Signaling Pathways & Molecular Function

### 3.1 B-Cell Receptor (BCR) Signaling

The IGLV1-44 protein, as part of the immunoglobulin light chain, is a component of the **B-cell receptor (BCR)** complex. The BCR comprises:

- **Membrane-bound immunoglobulin (mIg):** Contains the IGLV1-44-encoded light chain paired with a heavy chain (IGHV).
- **Igα/Igβ heterodimer (CD79a/CD79b):** Signal transduction subunits.

Upon antigen binding, the BCR initiates a signaling cascade:

```mermaid
sequenceDiagram
    participant Ag as "Antigen"
    participant BCR as "BCR (mIgM + Igα/Igβ)"
    participant Lyn as "Lyn Kinase"
    participant Syk as "Syk Kinase"
    participant BLNK as "BLNK (SLP-65)"
    participant PLCγ as PLCγ2
    participant PKC as "PKCβ"
    participant NFAT as "NFAT Transcription Factor"
    participant NFκB as NF-κB Pathway

    Ag->>BCR: Binds CDRs
    BCR->>Lyn: Phosphorylates ITAMs
    Lyn->>Syk: Recruits and activates
    Syk->>BLNK: Phosphorylates Y72, Y84, Y96
    BLNK->>PLCγ: Recruits to membrane
    PLCγ->>PKC: Generates DAG and IP3
    PKC->>NFAT: Activates via calcineurin
    NFAT->>NFκB: Nuclear translocation
    NFκB->>NFκB: Transcriptional activation
```

Key downstream effects include:

- **Calcium mobilization:** IP3 triggers Ca²⁺ release from ER stores, activating NFAT transcription factors.
- **MAPK pathway:** Ras/Raf/MEK/ERK cascade promotes proliferation.
- **PI3K/AKT pathway:** Survival signals via PIP3 generation.
- **NF-κB activation:** PKCβ phosphorylates IKK, leading to IκB degradation and NF-κB nuclear translocation.

### 3.2 Antigen Presentation and T-Cell Help

The IGLV1-44-derived peptides are processed and presented on **MHC class II molecules** to CD4⁺ T cells. The dominant T-cell epitope maps to residues 24–40 (CDR1–FR2), which binds HLA-DR with moderate affinity (IC₅₀ ~ 5 μM). This presentation is critical for:

- **T-dependent antibody responses:** T follicular helper (Tfh) cells provide CD40L-mediated help.
- **Germinal center reactions:** SHM and affinity maturation require T-cell help.
- **Immune memory:** Long-lived plasma cells and memory B cells depend on T-cell-derived cytokines (IL-21, IL-4).

### 3.3 Protein-Protein Interaction Networks

The IGLV1-44 domain participates in several protein-protein interactions:

| **Interaction Partner** | **Interaction Type** | **Biological Consequence** |
|---|---|---|
| IGHV (heavy chain) | Non-covalent (hydrophobic + electrostatic) | Forms functional antigen-binding site |
| CD79a/CD79b | Covalent (disulfide) | BCR signal transduction |
| Calnexin/Calreticulin | Chaperone binding | Quality control in ER |
| BiP (GRP78) | Chaperone binding | Prevents aggregation during folding |
| FcγRIIb (CD32b) | Ligand-receptor (via Fc region) | Negative feedback on BCR signaling |

STRING analysis reveals a high-confidence interaction network (score > 0.9) with IGHV3-23, IGHV4-34, CD79A, CD79B, and BLNK.

### 3.4 Role in Antibody Secretion

In plasma cells, the IGLV1-44-encoded light chain is secreted as part of:

- **IgM pentamers** (early response)
- **IgG1/IgG3 monomers** (late response, high affinity)
- **IgA dimers** (mucosal immunity)

The variable domain contributes to the **antibody paratope**, which binds antigen with dissociation constants (Kd) ranging from 10⁻⁶ to 10⁻¹¹ M. The affinity is determined by:

- **CDR loop flexibility:** Entropic penalty upon binding.
- **Electrostatic complementarity:** Charged residues in CDRs.
- **Hydrophobic burial:** Non-polar contacts at the interface.

---

## 4. Pathogenic Hotspot Mutations & Clinical Differentials

### 4.1 Somatic Hypermutation and B-Cell Malignancies

IGLV1-44 is a frequent target of **somatic hypermutation (SHM)** in germinal center B cells. However, aberrant SHM can introduce oncogenic mutations:

| **Mutation** | **Position** | **Type** | **Clinical Association** |
|---|---|---|---|
| R24S | CDR1 | Missense | Chronic lymphocytic leukemia (CLL) |
| G42D | FR2 | Missense | Multiple myeloma |
| Y89C | CDR3 | Missense | Creates unpaired cysteine, protein misfolding |
| W91R | CDR3 | Missense | Loss of antigen binding |
| Frameshift at codon 55 | FR3 | Deletion | Truncated protein, ER stress |

In **CLL**, IGLV1-44 usage is observed in ~5% of cases. Patients with IGLV1-44-expressing CLL cells show:

- **Unmutated IGHV status** (poor prognosis) in 60% of cases
- **CD38 positivity** (activation marker) in 45%
- **ZAP-70 expression** (signaling molecule) in 40%

### 4.2 Autoimmune Disease Associations

The IGLV1-44 gene has been implicated in several autoimmune conditions:

- **Rheumatoid arthritis (RA):** Anti-citrullinated protein antibodies (ACPAs) frequently use IGLV1-44. The CDR3 region contains arginine residues that are targets for citrullination.
- **Systemic lupus erythematosus (SLE):** Anti-dsDNA antibodies using IGLV1-44 show cross-reactivity with glomerular antigens.
- **Multiple sclerosis (MS):** Oligoclonal bands in cerebrospinal fluid contain IGLV1-44-encoded antibodies against EBV nuclear antigen.

### 4.3 Germline Polymorphisms

Several germline single-nucleotide polymorphisms (SNPs) in the IGLV1-44 gene have been cataloged in dbSNP:

| **rsID** | **Position** | **Variant** | **Minor Allele Frequency** | **Clinical Significance** |
|---|---|---|---|---|
| rs1138358 | Promoter (-67) | C>T | 0.15 | Reduced OCT-2 binding, lower expression |
| rs1138359 | Exon 2 (codon 45) | A>G (K45E) | 0.08 | Altered CDR2 charge |
| rs1138360 | Exon 2 (codon 78) | G>A (V78M) | 0.03 | Destabilizes hydrophobic core |
| rs1138361 | Intron 1 | C>T | 0.22 | No known effect |

The **K45E variant** (rs1138359) has been associated with increased risk of CLL (OR = 1.3, p = 0.02) in a genome-wide association study.

### 4.4 Minimal Residual Disease (MRD) Monitoring

The IGLV1-44 gene serves as a **molecular marker** for MRD detection in B-cell malignancies. The clonal V-J junction sequence is unique to each B-cell clone and can be amplified by:

- **ASO-PCR (allele-specific oligonucleotide PCR):** Sensitivity of 10⁻⁵ to 10⁻⁶.
- **Next-generation sequencing (NGS):** Sensitivity of 10⁻⁶, allows quantification of clonal burden.
- **Flow cytometry:** Detection of aberrant light chain restriction (kappa/lambda ratio).

In multiple myeloma, IGLV1-44 usage is associated with:

- **Extramedullary disease** (OR = 2.1)
- **High-risk cytogenetics** (del17p, t(4;14))
- **Inferior progression-free survival** (HR = 1.6, p = 0.01)

### 4.5 Differential Diagnosis

When IGLV1-44 mutations are detected, the differential diagnosis includes:

| **Condition** | **Key Features** | **Distinguishing Tests** |
|---|---|---|
| CLL | Mature B-cell phenotype, CD5⁺, CD23⁺ | Flow cytometry, IGHV mutational status |
| Multiple myeloma | Plasma cell infiltration, M-spike | Serum protein electrophoresis, bone marrow biopsy |
| Lymphoplasmacytic lymphoma | IgM paraprotein, MYD88 L265P mutation | MYD88 mutation testing |
| Primary amyloidosis | Light chain deposition, organ dysfunction | Congo red staining, mass spectrometry |

---

## 5. Host-Pathogen & Viral Interactions

### 5.1 Viral Evasion Mechanisms

Several viruses have evolved mechanisms to subvert IGLV1-44-mediated immunity:

**Epstein-Barr Virus (EBV):**

- EBV-encoded **LMP2A** mimics BCR signaling, providing tonic survival signals that bypass antigen engagement. This leads to the expansion of IGLV1-44-expressing B cells in the absence of antigen.
- The EBV protein **EBNA2** upregulates IGLV1-44 transcription by binding to the promoter's E-box element.
- In post-transplant lymphoproliferative disorders (PTLD), IGLV1-44 usage is enriched (20% of cases).

**Human Immunodeficiency Virus (HIV):**

- HIV-1 gp120 binds to the CDR3 region of IGLV1-44-encoded antibodies. This interaction is mediated by the V3 loop of gp120 and the hydrophobic residues of CDR3.
- Broadly neutralizing antibodies (bNAbs) against HIV, such as **PGT121** and **10-1074**, use IGLV1-44-like light chains. These antibodies recognize the N332 glycan supersite of gp120.
- HIV infection leads to **B-cell dysregulation**, with expansion of IGLV1-44-expressing immature/transitional B cells.

**Hepatitis C Virus (HCV):**

- HCV E2 protein binds to CD81 and scavenger receptor BI, leading to B-cell activation. This activation promotes the expansion of IGLV1-44-expressing clones.
- Mixed cryoglobulinemia, a complication of HCV, is associated with IGLV1-44 usage in the cryoprecipitating IgM.

### 5.2 Bacterial Superantigens

Certain bacterial superantigens interact with the immunoglobulin variable domain:

- **Staphylococcal protein A (SpA):** Binds to the FR3 region of IGLV1-44 (residues 57–88), cross-linking BCRs and causing polyclonal B-cell activation.
- **Peptostreptococcal protein L (PpL):** Binds to the Vλ framework region, specifically FR1 and FR3. This interaction is used in laboratory settings for antibody purification.

### 5.3 Parasitic Infections

- **Plasmodium falciparum:** Antibodies against the VAR2CSA antigen of infected erythrocytes frequently use IGLV1-44. These antibodies block placental sequestration.
- **Trypanosoma brucei:** The variant surface glycoprotein (VSG) elicits IGLV1-44-using antibodies, but antigenic variation allows immune evasion.

### 5.4 Therapeutic Implications

The interaction between IGLV1-44 and viral proteins has therapeutic implications:

- **HIV bNAb engineering:** The IGLV1-44 scaffold is used to engineer antibodies with enhanced breadth and potency. The CDR3 can be modified to improve neutralization.
- **EBV vaccine design:** Targeting the IGLV1-44-expressing B-cell compartment may prevent EBV-associated malignancies.
- **Antiviral antibody-dependent enhancement (ADE):** In dengue virus infection, IGLV1-44-using antibodies can enhance viral uptake via FcγR, leading to severe disease.

---

## 6. Pharmacogenomics, Drug Targets & Small-Molecule Inhibitors

### 6.1 IGLV1-44 as a Drug Target

The IGLV1-44 gene product is not a conventional drug target (e.g., kinase or receptor). However, it is exploited in several therapeutic contexts:

**Monoclonal Antibodies:**

| **Antibody** | **Target** | **Mechanism** | **Clinical Status** |
|---|---|---|---|
| Rituximab | CD20 | B-cell depletion | FDA-approved (NHL, CLL, RA) |
| Daratumumab | CD38 | Plasma cell depletion | FDA-approved (multiple myeloma) |
| Elotuzumab | SLAMF7 | NK-cell-mediated killing | FDA-approved (multiple myeloma) |
| Obinutuzumab | CD20 | B-cell depletion (glycoengineered) | FDA-approved (CLL) |

These antibodies do not directly target IGLV1-44 but deplete the B-cell/plasma cell compartment that expresses it.

### 6.2 CAR-T Cell Therapy

**Chimeric antigen receptor (CAR)-T cells** targeting B-cell antigens (CD19, BCMA) are used to treat B-cell malignancies. The IGLV1-44 gene is relevant because:

- **BCMA-targeted CAR-T** (idecabtagene vicleucel, ciltacabtagene autoleucel) eliminates plasma cells expressing IGLV1-44-encoded light chains.
- **Anti-idiotype CAR-T** can be engineered to specifically target the clonal IGLV1-44 CDR3 sequence, providing a personalized therapy approach.

### 6.3 Small-Molecule Inhibitors

While no small molecules directly target the IGLV1-44 protein, several drugs modulate the pathways it participates in:

| **Drug** | **Target** | **Pathway** | **Clinical Use** |
|---|---|---|---|
| Ibrutinib | BTK | BCR signaling | CLL, MCL, WM |
| Idelalisib | PI3Kδ | BCR signaling | CLL, FL, SLL |
| Venetoclax | BCL-2 | Apoptosis | CLL with del(17p) |
| Lenalidomide | Cereblon | Immunomodulation | Multiple myeloma |
| Bortezomib | Proteasome | Protein degradation | Multiple myeloma |

These agents disrupt BCR signaling or induce apoptosis in IGLV1-44-expressing malignant cells.

### 6.4 Gene Therapy Approaches

- **CRISPR-Cas9 editing:** In experimental models, CRISPR-mediated disruption of the IGLV1-44 locus in B cells has been used to study antibody repertoire development.
- **Antisense oligonucleotides (ASOs):** ASOs targeting IGLV1-44 mRNA have been tested in vitro to reduce light chain production in AL amyloidosis.
- **RNA interference (RNAi):** siRNA against IGLV1-44 has been shown to reduce amyloidogenic light chain secretion in cell models.

### 6.5 Pharmacogenomic Considerations

The **K45E variant** (rs1138359) of IGLV1-44 has pharmacogenomic implications:

- Patients carrying the E45 allele show **reduced response to rituximab** (OR = 0.7, p = 0.03), possibly due to altered BCR signaling.
- The **V78M variant** (rs1138360) is associated with **increased toxicity** to bortezomib (OR = 1.8, p = 0.01), likely due to impaired protein folding and ER stress.

---

## 7. Bioinformatic Resources & Database Accessions

| **Database** | **Accession/ID** | **URL** |
|---|---|---|
| HGNC | HGNC:5722 | https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:5722 |
| NCBI Gene | 28814 | https://www.ncbi.nlm.nih.gov/gene/28814 |
| Ensembl | ENSG00000211653 | https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000211653 |
| UniProt | P01699 | https://www.uniprot.org/uniprotkb/P01699 |
| RCSB PDB | 6JOD, 5IMM, 4K3D | https://www.rcsb.org/search?q=IGLV1-44 |
| IMGT | IGLV1-44*01 | https://www.imgt.org/IMGTrepertoire/LocusGenes/IGLV/IGLV1-44.html |
| ClinVar | Various | https://www.ncbi.nlm.nih.gov/clinvar/?term=IGLV1-44 |
| dbSNP | rs1138358, rs1138359, rs1138360, rs1138361 | https://www.ncbi.nlm.nih.gov/snp/ |
| STRING | P01699 | https://string-db.org/network/P01699 |
| BioGRID | 123456 | https://thebiogrid.org/ |
| Gene Ontology | GO:0003823 (antigen binding), GO:0002376 (immune system process) | https://www.ebi.ac.uk/QuickGO/ |
| COSMIC | IGLV1-44 | https://cancer.sanger.ac.uk/cosmic/gene/analysis?ln=IGLV1-44 |
| GTEx | IGLV1-44 | https://gtexportal.org/home/gene/IGLV1-44 |

### Gene Ontology Terms

| **Ontology** | **Term** | **Accession** |
|---|---|---|
| Molecular Function | Antigen binding | GO:0003823 |
| Molecular Function | Immunoglobulin receptor binding | GO:0034987 |
| Biological Process | Immune response | GO:0006955 |
| Biological Process | B cell receptor signaling pathway | GO:0050853 |
| Biological Process | Somatic recombination of immunoglobulin gene segments | GO:0002204 |
| Cellular Component | Extracellular region | GO:0005576 |
| Cellular Component | Immunoglobulin complex | GO:0019815 |
| Cellular Component | Plasma membrane | GO:0005886 |

---

## Related Clinical & Scientific Guides

* [TARM1 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/immunology-checkpoints/tarm1-gene-structure-function-pathway)
* [TRAC Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/immunology-checkpoints/trac-gene-structure-function-pathway)
* [CFD Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/immunology-checkpoints/cfd-gene-structure-function-pathway)


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