### Gene Overview

**Gene Symbol:** FTCD  
**Gene Name:** Formiminotransferase-Cyclodeaminase  
**Location:** Human chromosome 6q22.1

The FTCD gene encodes a bifunctional enzyme involved in the metabolism of histidine. The enzyme has both transferase and deaminase activities, facilitating the transfer of one-carbon units from formiminoglutamate to the folate pool. This function is crucial for maintaining proper folate metabolism and cellular processes dependent on one-carbon units.

### 1. Associations with Other Genes
Although the provided summaries do not explicitly mention other genes associated with FTCD, it is important to note:
- **MTHFR (Methylenetetrahydrofolate Reductase):** Variants in this gene can influence overall folate metabolism and interact functionally with the metabolic pathways involving FTCD.
- **SHMT (Serine Hydroxymethyltransferase):** This gene is involved in the conversion of serine to glycine, which is also connected to one-carbon metabolism.
- **CTH (Cystathionine gamma-lyase):** This gene plays a role in the transsulfuration pathway and also affects homocysteine levels, which are influenced by folate metabolism.

### 2. Aging and Age-Related Diseases
- **Folate Metabolism and Neurodegenerative Conditions:** Since FTCD is essential in folate metabolism, disruptions in its function due to genetic mutations or age-related declines could result in inadequate folate levels. Low folate has been linked to various neurodegenerative diseases such as Alzheimer's disease and cognitive decline.
- **Cancer Risk:** Aberrant one-carbon metabolism has been associated with certain cancers, and mutations in the FTCD gene could potentially influence susceptibility to age-related malignancies.
- **Cardiovascular Health:** Elevated homocysteine levels, which can be influenced by folate and 1-carbon metabolism, are linked to increased risks of cardiovascular diseases, which are more prevalent with aging.

### 3. Drug Interactions
While there are no specific drugs explicitly stated to interact directly with the FTCD gene or protein, the following categories may be relevant due to the gene's involvement in folate metabolism:
- **Folic Acid Supplements:** These can have a significant impact on folate levels in the body and are often administered as part of health plans for individuals with identified deficiencies or related conditions.
- **Methotrexate:** A folate antagonist, it could theoretically affect methionine metabolism pathways in which FTCD enzyme activity is involved. Monitoring of folate status would be particularly important in patients receiving this drug.

### 4. Pathways and Biological Processes
FTCD is involved in several important biological pathways:
- **Histidine Metabolism:** The gene encodes enzymes necessary for proper processing of histidine, converting it into important metabolic products.
- **One-Carbon Metabolism:** FTCD plays a significant role in the transfer and transformation of one-carbon units, which are critical for nucleotide synthesis and amino acid metabolism.
- **Folate Biosynthesis and Metabolism:** This gene directly contributes to canalizing metabolic flows into the folate pool, essential for cellular flux and homeostasis.

### Conclusion
FTCD is a vital gene related to one-carbon metabolism and folate homeostasis. Alterations in its function can play significant roles in aging, age-related diseases, and overall metabolic health. Understanding these interactions and associations is crucial for elucidating the gene's broader biological implications and potential clinical significance.