Pork (IMAGE) Uppsala University Caption This is fat and lean pork chop. The mutation in the IGF2 gene that disrupts the interaction with the ZBED6 protein has a major effect on the relative proportion of fat and muscle in pigs. Credit Photo: Ingemar Hansson. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.