ABCA1 is a protein that plays a crucial role in lipid metabolism, particularly in the transport of cholesterol and phospholipids. It is primarily found in the liver and intestines, where it helps to remove excess cholesterol from cells and transport it to high-density lipoprotein (HDL) particles, often referred to as "good cholesterol." This process is essential for maintaining healthy cholesterol levels in the body. Mutations in the ABCA1 gene can lead to various health issues, including Tangier disease, a rare genetic disorder characterized by low levels of HDL cholesterol and the accumulation of cholesterol in tissues. Understanding the function of ABCA1 is important for developing treatments for cardiovascular diseases and other conditions related to lipid metabolism.