SLC22A2 is a gene that provides instructions for making a protein known as a solute carrier. This protein is primarily found in the liver and kidneys and plays a crucial role in transporting various substances, including drugs and organic compounds, across cell membranes. Mutations in the SLC22A2 gene can lead to altered transport functions, which may affect how the body processes certain medications. This can have implications for drug efficacy and toxicity, making it an important area of study in pharmacogenomics, the field that examines how genes influence individual responses to drugs.