### HLA-DQB2 Gene Overview

**Gene Symbol:** HLA-DQB2  
**Family:** HLA Class II Beta Chain Paralogs  
**Role:** Component of the MHC Class II molecule, involved in peptide presentation to CD4 T-cells, critical for the adaptive immune response.

### 1. Associated Genes
Beyond the genes mentioned in your summary (such as HLA-DQA), other genes associated with HLA-DQB2 include:

- **HLA-DRB1:** Another beta chain component involved in MHC Class II molecules.
- **HLA-DMA and HLA-DMB:** These genes encode proteins that assist in the loading of peptides onto MHC Class II proteins (HLA-DQ and HLA-DR molecules).
- **CD74:** Encodes the invariant chain involved in stabilizing MHC Class II molecules in the endoplasmic reticulum.

### 2. Aging and Age-Related Diseases
The involvement of HLA-DQB2 in age-related diseases can be potentially linked through:

- **Autoimmune diseases:** Certain polymorphisms within the HLA-DQ region, including HLA-DQB2, have been associated with conditions like rheumatoid arthritis and multiple sclerosis, which can manifest or become more pronounced with age.
- **Immunosenescence:** The aging immune system shows a decrease in the functionality of T-cells, which may relate to changes in MHC Class II expression, including HLA-DQB2.

### 3. Drug Interactions
While HLA-DQB2 itself may not have specific drug interactions, *drugs that target pathways involving antigen presentation or autoimmune conditions* could be relevant. Potentially related drug classes include:

- **Immunosuppressants:** Such as corticosteroids or drugs like azathioprine, which modulate immune responses that include MHC Class II activity.
- **Biologics:** Targeting pathways in autoimmune conditions linked with HLA genotypes.
  
Recent FDA-approved biologics such as monoclonal antibodies targeting specific immune pathways (e.g., anti-TNF agents) may indirectly relate to modulation of HLA-related functions.

### 4. Pathways and Biological Processes
HLA-DQB2 is involved in several key biological processes and pathways, including but not limited to:

- **Antigen Processing and Presentation:** HLA-DQB2 is crucial for presenting processed antigenic peptides to CD4+ T-cells, facilitating adaptive immune responses.
- **Immune System Process:** It plays a role in the broader immune response and cellular signaling pathways associated with T-cell activation.
- **Cellular Response to Type I Interferon:** Appropriate expression of MHC Class II molecules is modulated by interferon signaling pathways in response to cytokines.
  
Other relevant pathways may include those involved in **cellular stress responses** and **endosomal-lysosomal trafficking**, which are important for processing antigens for MHC presentation.

### Conclusion
HLA-DQB2 is an integral component of the immune system that participates in the presentation of extracellular antigens to the adaptive immune response, and its involvement in genetic variations can influence susceptibility to various diseases, particularly autoimmune conditions. Though direct drug interactions are less frequently noted, the gene has broader implications in the pharmacological modulation of immune responses.