CPT1, or Carnitine Palmitoyltransferase 1, is an enzyme located in the outer mitochondrial membrane. It plays a crucial role in the metabolism of fatty acids by facilitating the transport of long-chain fatty acids into the mitochondria, where they are oxidized for energy production. This process is essential for maintaining energy balance in the body. There are two main forms of CPT1: CPT1A, primarily found in the liver, and CPT1B, which is mainly present in muscle tissues. Deficiencies or mutations in the CPT1 gene can lead to metabolic disorders, affecting the body's ability to utilize fats for energy, particularly during fasting or prolonged exercise.