The PNPLA3 gene provides instructions for making a protein which is found in fat cells (adipocytes) and liver cells (hepatocytes). The liver is a part of the digestive system that helps break down food, store energy, and remove waste products, including toxins. The function of the PNPLA3 protein is not well understood, but it is thought to help regulate the development of adipocytes and the production and breakdown of fats (lipogenesis and lipolysis) in hepatocytes and adipocytes. Studies indicate that the activity (expression) of the PNPLA3 gene decreases during periods without food (fasting) and increases after eating, suggesting that the amount of PNPLA3 protein produced is regulated as needed to help process and store fats in the diet.