Permanent phenotypic correction of Haemophilia B in immunocompetent mice by prenatal gene therapy Running title: Permanent correction of haemophilia in a fetal mouse model

Gene Therapy Research Group, Section of Cell and Molecular Biology, Imperial College London, London, SW7 2AZ, UK Molecular Immunology Unit, Institute of Child Health, University College London, London, WC1N 1EH, UK Haemostasis and Thrombosis, MRC Clinical Sciences Centre, Imperial College London, London, W12 0NN, UK Renal Medicine Section, Faculty of Medicine, Imperial College London, London, W12 0NN Oxford BioMedica (UK) Ltd, Oxford, OX4 4GA, UK Histopathology Unit, Cancer Research UK, London UK, WC2A 3PX Department of Molecular Genetics, Institute of Ophthalmology, University College London, London, EC1V 9EL, UK