Albertine Donker

IRIDA: a Heterogeneous Disease 163 4 Authorship Contribution: A.E.D is a pediatric hematologist and PhD candidate who collected data, analyzed results, reviewed the literature and drafted the manuscript, with help of C.C.S. and T.M.A.P. V.M.J.N, M.F.R, A.W.R, I.M.A, A.J.V, A.B.V, M.G, B.G, M.C.H.J, A.J.M.R, F.L.V, M.R.N, L.T.V, P.P.T.B. are clinicians who diagnosed and treated the patients and provided clinical data for this paper. R.S. and B.L.P. H. are geneticists who coordinated the genotyping of patients and drafted the genetic part of the paper. D.L.B is a clinical chemist who provided data for this study. D.W.S initiated and coordinated the project. All authors approved the final version of the manuscript. Acknowledgements We thank Tineke Smilde and Wilfred Hurkx for kindly providing us with patient data. We also thank Siem Klaver for his help in building the database.