1. Rheumatology and Bone Disease Unit (S.H.R.), Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh,Western General Hospital, Edinburgh, United Kingdom; Hospital el Bierzo (L.C.-G.), Ponferrada, Spain; Department of Medicine (W.D.F.), University of E Anglia, Norwich, United Kingdom; Department of Internal Medicine (L.G.), Department of