Hartnup disorder is a rare genetic condition that affects the body's ability to absorb certain amino acids, particularly tryptophan, from food. This disorder is caused by mutations in the SLC6A19 gene, which plays a crucial role in transporting these amino acids in the intestines and kidneys. As a result, individuals with Hartnup disorder may experience symptoms such as skin rashes, neurological issues, and gastrointestinal problems. The condition is often managed through dietary changes, including increased protein intake and supplementation of specific amino acids. While Hartnup disorder can lead to various health challenges, many individuals can lead normal lives with proper care and monitoring.