Sequence 54 from Patent WO0125466. Sequence 13 from Patent WO0175135. Sequence 71 from Patent WO0175135. Sequence 18 from Patent WO0179518. PRODUCER CELL FOR THE PRODUCTION OF RETROVIRAL VECTORS. CODON OPTIMISATION FOR EXPRESSION IN RETROVIRUS PACKAGING CELLS. Retinoic acid receptor beta-2, its antagonists, and gene therapy vectors for the treatment of neurological disorders. Retinoic acid receptor beta-2, its antagonists, and gene therapy vectors for the treatment of neurological disorders.