### HSD17B4 Gene Overview

**Gene Symbol:** HSD17B4

#### General Function
The HSD17B4 gene encodes a bifunctional enzyme that plays a crucial role in the peroxisomal beta-oxidation pathway for fatty acids. This enzyme facilitates the conversion of 2-enoyl-CoA into 3-hydroxyacyl-CoA and subsequently dehydrogenates 3-hydroxyacyl-CoA to 3-ketoacyl-CoA. These reactions are fundamental for the degradation of fatty acids, including straight-chain and 2-methyl-branched-chain fatty acids, as well as some bile acid intermediates.

### 1. Associated Genes
While specific genes directly associated with HSD17B4 were not mentioned in the summaries, it may interact with other genes related to fatty acid metabolism and peroxisomal function. For example:
- **ACOX1 (Acyl-CoA oxidase 1):** Another key enzyme in the peroxisomal pathway.
- **EHHADH (Enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase):** Involved in fatty acid degradation.
- **SCP2 (Sterol carrier protein 2):** Involved in lipid transport and metabolism.
- **CPT1A (Carnitine palmitoyltransferase 1A):** Related to mitochondrial fatty acid transport, indirectly linked to peroxisomal functions.

### 2. Aging and Age-Related Diseases
- **D-bifunctional Protein Deficiency (DBPD):** Mutations in HSD17B4 can lead to DBPD, characterized by accumulation of fatty acids and their metabolites, potentially impacting energy metabolism in tissues, including those affected by age-related degeneration.
- **Lipid Metabolism in Aging:** Alterations in lipid metabolism, including perturbations in peroxisomal fatty acid oxidation, can influence age-related diseases, such as metabolic syndrome and cardiovascular diseases.
- **Role in Neurodegeneration:** Impaired fatty acid metabolism has been implicated in neurodegenerative diseases, with potential associations between HSD17B4 function and conditions like Alzheimer's disease.

### 3. Drug Interactions
Currently, specific drugs or drug classes known to interact directly with the HSD17B4 gene product or its function have not been well characterized. However, it is important to note:
- Drugs that affect fatty acid metabolism or peroxisomal function could theoretically interact with HSD17B4.
- Statins, which are known to affect lipid metabolism, may indirectly relate to pathways in which HSD17B4 is involved, though no direct interactions have been established in the literature.

### 4. Pathways and Biological Processes
The HSD17B4 gene participates in several biological pathways:
- **Fatty Acid β-Oxidation:** A major metabolic pathway leading to the breakdown of fatty acids, where HSD17B4 has a direct enzymatic role.
- **Peroxisome Function:** Essential for lipid metabolism, detoxification processes, and cellular homeostasis related to fatty acids and metabolic intermediates.
- **Steroid Hormone Biosynthesis:** HSD17B4 may also play a role in steroid metabolism due to its 17-beta-hydroxysteroid dehydrogenase activity, relevant in the biosynthesis and metabolism of steroids, influencing various physiological processes.

**Conclusion:** The HSD17B4 gene is integral to fatty acid metabolism, with wide implications for energy homeostasis, metabolic diseases, and potentially age-related conditions. Ongoing research may further elucidate its role in health and disease, particularly concerning lipid metabolism.