[1] Charite Univ Med Berlin, Dept Biochem, Berlin, Germany
[2] Free Univ Berlin, Berlin, Germany
[3] Humboldt Univ, Berlin, Germany
[4] Charite Univ Med Berlin, Core Facil High Throughput Mass Spectrometry, Berlin, Germany
[5] SCIEX Ltd, Concord, ON, Canada
[6] Univ Oxford, Wellcome Ctr Human Genet, Nuffield Dept Med, Oxford, England