D-bifunctional Protein Deficiency is a rare genetic disorder that affects the body's ability to break down certain fats, specifically very long-chain fatty acids. This condition is caused by mutations in the HSD17B4 gene, which is responsible for producing an enzyme that plays a crucial role in fatty acid metabolism. As a result, individuals with this deficiency may experience a buildup of toxic substances in the body, leading to various health issues. Symptoms of D-bifunctional Protein Deficiency can vary widely but often include liver dysfunction, muscle weakness, and neurological problems. Early diagnosis and management are essential to prevent complications. Treatment typically involves dietary changes and supplementation to help manage the condition and improve quality of life.