The epimerase activity is highly expressed in the spleen, stomach, uterus, ovary, kidney and lung. In the brain, the activity is low and no activity is found in serum 21. By analyzing the total activity in tissues and mouse embryonic fibroblasts of DS-epi1−/− and DS-epi2−/− mice, it is possible to show that DS-epi1 is the predominant epimerase in most tissues, whereas DS-epi2 is the main epimerase in the brain 21,22. DS-epi2 also has a relatively high expression in the kidney.
