KCNJ5 is a gene that provides instructions for making a protein known as an ion channel. This protein is primarily found in the cells of the heart and kidneys, where it helps regulate the flow of potassium ions. Proper functioning of KCNJ5 is essential for maintaining the electrical activity of the heart and balancing fluid levels in the body. Mutations in the KCNJ5 gene can lead to various health issues, including a condition called primary hyperaldosteronism, which can cause high blood pressure. Understanding KCNJ5 is important for researchers studying cardiovascular health and related disorders.