1 Section of Medical Genetics, Department of Laboratory Medicine, Telemark Hospital, 3710 Skien, Norway ; Head and Neck Research Group, Research Centre, Akershus University Hospital, Lørenskog, Norway ; Campus Akershus University Hospital, University of Oslo, Nordbyhagen, Norway.
2 Section of Medical Genetics, Department of Laboratory Medicine, Telemark Hospital, 3710 Skien, Norway.
3 Head and Neck Research Group, Research Centre, Akershus University Hospital, Lørenskog, Norway ; Campus Akershus University Hospital, University of Oslo, Nordbyhagen, Norway.