Department of Endocrinology, Metabolism and Diabetes, Metabolism Unit, Center for Endocrinology, Metabolism, and Diabetes, Karolinska Institute at Karolinska University Hospital Huddinge, S-141 86, Stockholm, Sweden. mats.rudling@ki.se. Department of Medicine, and Molecular Nutrition Unit, Karolinska Institute at Karolinska University Hospital Huddinge, S-141 86, Stockholm, Sweden. mats.rudling@ki.se. Department of Biosciences and Nutrition, Karolinska Institute at Karolinska University Hospital Huddinge, S-141 86, Stockholm, Sweden. mats.rudling@ki.se. Mayo Clinic, Rochester, MN, USA. camilleri.michael@mayo.edu. Albireo, Göteborg, Sweden. Hans.Graffner@albireopharma.com. NNF Center for Basic Metabolic Research, the Panum Institute, University of Copenhagen, Copenhagen, Denmark. jjholst@sund.ku.dk. Albireo, Göteborg, Sweden. Leif.Rikner@albireopharma.com.