Galactose-1-phosphate uridylyltransferase is an enzyme that plays a crucial role in the metabolism of galactose, a sugar found in milk and dairy products. It catalyzes the conversion of galactose-1-phosphate and uridine diphosphate (UDP) into glucose-1-phosphate and uridine monophosphate (UMP). This reaction is essential for the proper utilization of galactose in the body. Deficiency of this enzyme can lead to a condition known as galactosemia, which can cause serious health issues if not managed properly. Individuals with this condition cannot effectively process galactose, leading to its accumulation in the body. Early diagnosis and dietary management are critical to prevent complications associated with this metabolic disorder.