1. Reykjavik Primary Health Care, Glaesibaer, Reykjavik, Iceland
2. University of Iceland, Reykjavík, Iceland
3. The Blood Bank, Landspitali University Hospital, Reykjavík, Iceland
4. Department of Genetics and Molecular Medicine, Landspitali University Hospital
5. Department of Biochemistry and Molecular Biology, BioMedical Center, University of Iceland, 101 Reykjavik, Iceland