The PSAT1P3 gene is a pseudogene located on chromosome 1 and is associated with various functions related to metabolism and cellular processes. Here's a comprehensive overview based on your request:

### Gene Information
- **Gene Symbol**: PSAT1P3
- **Type**: Pseudogene related to PSAT1 (phosphoserine aminotransferase 1)

### 1. Associated Genes
While the immediate relationships of PSAT1P3 are mainly with the PSAT1 gene, pseudogenes can often have regulatory roles or share sequence similarity with other genes. However, specific information on additional direct associations isn't widely reported in the literature for PSAT1P3. Generally, genes functionally linked to PSAT1 in various pathways may also be considered indirectly associated, such as:
- PSAT1: The main protein-coding gene it relates to, involved in serine biosynthesis.
- Other genes involved in metabolic pathways may have overlapping regulatory mechanisms.

### 2. Aging and Age-Related Diseases
Current literature does not provide extensive direct evidence linking the PSAT1P3 pseudogene to aging or age-related diseases. However, genes involved in serine metabolism, like PSAT1, have been studied for their roles in cellular homeostasis and metabolic regulation, which are relevant to aging and age-related conditions. Indirectly, abnormalities in these pathways can affect aging processes and diseases associated with aging.

### 3. Drug Interactions
As of now, there are no specific drugs or drug classes directly known to interact with PSAT1P3. However, given its association with PSAT1, metabolic pathways often linked to treatments involving:
- Antimetabolites (drugs affecting nucleic acid metabolism)
- Enzyme inhibitors in metabolic regulatory pathways might be implicated.

Further research could reveal more about the pharmacological implications involving this pseudogene.

### 4. Pathways and Biological Processes
PSAT1P3 is classified as a pseudogene and may not have defined pathways. However, its locus can influence or regulate pathways potentially related to:
- **Serine Biosynthesis**: The main biological process involving PSAT1, as a pseudogene, could impact metabolic regulation indirectly.
- **Amino Acid Metabolism**: As a member of the PSAT family, implications in the broader amino acid metabolism pathways can be hypothesized.

The impact of pseudogenes is often regulatory, influencing the expression of their functional counterparts or related genes through mechanisms like RNA interference rather than having direct functional annotations.

### Current Research and Future Directions
Further studies are needed to elucidate the specific roles of PSAT1P3 and its potential implications in metabolic disorders, aging processes, and therapeutic targets. Understanding the impact of non-coding and pseudogenes on gene regulation may provide new insights into genetics and disease mechanisms.

### Summary
The PSAT1P3 gene is a pseudogene with limited direct functional annotations but potentially significant implications in metabolic regulation through its association with PSAT1. While research on its role in aging and drug interactions is sparse, it warrants further investigation to clarify its biological significance.