1. Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
2. University of Basel, Petersplatz 1, 4001 Basel, Switzerland.
3. SIB Swiss Institute of Bioinformatics, 4058 Basel, Switzerland.
4. Institute of Medical Sciences, University of Aberdeen, AB25 2ZD Aberdeen, UK.