Sequence 53 from Patent WO0125466. Sequence 12 from Patent WO0175135. Sequence 70 from Patent WO0175135. Sequence 5 from Patent WO0179518. Sequence 6 from patent US 6969598. 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.