### WDR90 Gene Overview

**Gene Symbol**: WDR90  
**Function**: The WDR90 gene is primarily associated with the formation and assembly of cilia, notably the primary cilium, which plays critical roles in various signaling pathways and cellular homeostasis. 

### Additional Associations

1. **Associated Genes**:
   - **Ift88**: Involved in intraflagellar transport, crucial for ciliary assembly and function.
   - **Kif3a**: A kinesin protein important for the transport of proteins to cilia.
   - **Tg737**: Known for its role in cilia biogenesis and related disorders.
   - **Dync2h1**: A gene that encodes a dynein involved in ciliary transport.
   - **Bbs1**: Related to Bardet-Biedl syndrome, involving ciliary functions.

### Aging and Age-Related Diseases

2. **Aging and Disease Associations**:
   - Research indicates that ciliary dysfunction, where WDR90 is involved, is linked to age-related conditions such as:
     - **Age-related macular degeneration (AMD)**: Abnormalities in retinal cilium function.
     - **Obesity and metabolic syndrome**: Related to altered signaling via primary cilia.
     - **Kidney diseases**: A dysfunction in cilia can lead to cystic kidney diseases (e.g., polycystic kidney disease).
   - Additionally, the role of primary cilia in sensing the cellular environment suggests potential implications in aging, where cellular response mechanisms may deteriorate.

### Drug Interactions

3. **Drugs and Drug Classes**:
   - Currently, there are no specific drugs directly targeting WDR90 reported in public databases. However, ciliary dysfunction is involved in broader conditions which may be treated with:
     - **Targeted therapies** for polycystic kidney disease (e.g., tolvaptan).
     - **Cholesterol-lowering agents**, as ciliary signaling is often linked to lipid metabolism.

### Biological Pathways

4. **Pathways and Biological Processes**:
   - **Cilium Assembly Pathway**: WDR90 is essential for the efficient assembly of primary cilia.
   - **Cell Cycle Regulation**: Cilia are involved in sensing the cell cycle, affecting processes like cell division and growth.
   - **Signaling Pathways**: WDR90 plays a role in Hedgehog and Wnt signaling pathways, which are critical for cellular communication, development, and tissue homeostasis.
   - **Intraflagellar Transport**: WDR90 is connected to pathways that govern the transport of materials necessary for cilia structure and function.
   - **Cellular Stress Response**: Connections exist regarding how cilia mediate responses to cellular stress, linking to aging processes.

### Conclusion

WDR90 is a key player in ciliary function, with implications in various biological processes and disorders. Further research into its specific interactions, roles in disease mechanisms, and potential therapeutic targets is warranted, especially in the context of aging and its associated conditions.