### GMNC Gene Overview
The GMNC (Geminin Cell Cycle Regulator) gene is crucial for the regulation of DNA replication and cell cycle processes. It is thought to play an important role in managing the initiation of chromosomal DNA replication and ensuring that it occurs at the right time and place within the cell.

### 1. Associated Genes
While the provided summaries mention TOPBP1, CDK2, and CDC45L in connection with GMNC, additional genes that may be associated with GMNC based on literature and functional studies include:
- **ORC1**: Origin recognition complex subunit 1, involved in the initiation of DNA replication.
- **PCNA**: Proliferating cell nuclear antigen, known for its role as a sliding clamp in DNA replication.
- **MCM proteins**: Minichromosome maintenance proteins, essential for DNA replication.
- **RB1**: Retinoblastoma 1, part of the cell cycle regulation network.

### 2. Age-Related Contributions
While specific studies directly linking GMNC to aging or age-related diseases may not be abundant, the gene's involvement in cell cycle regulation and DNA replication suggests that it could have implications in:
- **Cellular Senescence**: As cells age and undergo stress, proper replication control is crucial to prevent genomic instability, which is a hallmark of aging.
- **Cancer**: Abnormalities in DNA replication and cell cycle regulation are hallmarks of many cancers. Since GMNC is a regulator, its dysregulation could lead to tumorigenesis.
- **Developmental disorders**: Disruptions in cell cycle regulation during development may also be linked to age-related diseases and conditions.

### 3. Drug Interactions
No specific drugs or drug classes targeting GMNC have been well-established in available literature. However, drugs that target cell cycle regulation or DNA replication, such as:
- **CDK inhibitors**: Drugs such as Palbociclib (Ibrance) which inhibit cyclin-dependent kinases that interact with GMNC's regulatory functions on the cell cycle may indirectly affect GMNC activity.
  
Potential future studies involving GMNC may establish more direct interactions with specific therapeutic agents.

### 4. Involved Pathways & Biological Processes
GMNC is associated with a variety of pathways and biological processes, including:
- **DNA Replication**: Mediates the recruitment of replication factors to replication origins, particularly involving TOPBP1 and CDC45L.
- **Cell Cycle Checkpoints**: Plays a role in ensuring proper progression through the cell cycle, particularly during S phase.
- **Regulation of Cilium Assembly**: Suggested involvement in processes that may regulate cilia function and formation.
- **Cell Cycle Control Pathways**: It is implicated in various canonical pathways such as the cyclin-dependent kinase pathway that regulates the cell cycle and could contribute to tumorigenesis if dysfunctional.

### Conclusion
GMNC is a pivotal regulator of DNA replication and the cell cycle, interfacing with a variety of cellular processes and potential links to aging and diseases like cancer. Future studies may provide further insights into its role in pharmacological interactions and broader biological pathways.