### OR4S1 Gene Overview

**Gene Symbol**: OR4S1  
**Function**: The OR4S1 gene encodes an olfactory receptor that plays a crucial role in the detection of odorant molecules, which are binding to the olfactory receptor proteins in the nose. These interactions initiate neuronal responses that result in the perception of smell. 

**Protein Classification**: 
- Family: Olfactory receptors (part of the G-protein-coupled receptors, GPCRs)
- Structure: 7-transmembrane domain 

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### 1. Associated Genes
Olfactory receptors, including OR4S1, are part of a large gene family, and while they are generally categorized based on their functional context, specific associations outside of olfactory receptors usually include genes involved in olfactory signal transduction (such as G protein subunit genes). However, detailed specific genes that interact with OR4S1 beyond its closely related olfactory receptors are not typically specified in standard summaries. The overall olfactory receptor gene family includes:

- **OR genes** like OR4S1, OR5A1, OR2A4, etc.
  
**Note**: Functional associations to other genes could depend on specific alleles or variants which are more commonly found in specific populations or in certain research studies focusing on gene-gene interactions or regulatory networks.

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### 2. Aging and Age-Related Diseases

While olfactory receptors like OR4S1 are less directly studied in aging research, the sense of smell does often decline with age, a condition known as presbyosmia. Some studies suggest that olfactory dysfunction might be linked to age-related diseases such as:

- **Alzheimer's Disease**: Olfactory deficits may serve as early biomarkers for cognitive decline and neurodegenerative conditions. Certain olfactory receptor genes have been implicated in the changing olfactory perception associated with Alzheimer's.

- **Parkinson's Disease**: Anosmia (loss of smell) is a common early symptom of Parkinson’s disease, indicating potential relevance of the olfactory system and associated genes.

Developments in other GPCRs are being studied for their roles in neural signaling and potential impacts on aging, although specific studies targeting OR4S1 directly in the context of aging are sparse.

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### 3. Drug Interactions

Currently, there are no well-documented drugs or drug classes specifically known to interact with OR4S1. However, olfactory receptors have been explored in drug discovery as potential therapeutic targets for certain neurodegenerative diseases, since they participate in sensory perception and stereo-specific signaling. Some compounds designed to modulate GPCR activity might indirectly interact with olfactory receptors, but no specific drugs targeting OR4S1 are established.

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### 4. Pathways and Biological Processes

The primary biological processes that involve the OR4S1 gene include:

- **Olfactory Signaling Pathway**: OR4S1 is involved in the detection of odorants and contributes to the olfactory signal transduction cascade which utilizes G-proteins to relay signals from the external environment to the central nervous system.
  
- **G-Protein Coupled Receptor Pathway**: As a member of the GPCR family, OR4S1 participates in pathways related to cellular signaling and sensory perception.

- **Sensory Processing**: Essential in the biological process of sensory perception, particularly pertaining to the recognition and transduction of odor stimuli.

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In summary, while OR4S1 is significantly characterized by its role in olfaction, detailed research regarding its associations with specific genes, aging implications, drug interactions, and pathways is limited and largely inferential based on the common functions of olfactory receptors in general. Further research into the specific nuances of OR4S1 may reveal more targeted information.