The present invention relates, in part, to methods for large-scale purification of mRNA. The method includes, at least, a step of centrifuging an mRNA suspension in a centrifuge comprising a porous substrate at a speed sufficient to remove process contaminants and to precipitate purified mRNA composition onto the porous substrate.

The present disclosure is directed to compositions and methods for the treatment of Metabolic Liver Disorders. The compositions and methods can comprise an adeno-associated virus (AAV) piggyBac polynucleotide comprising a transgene. The transgene may comprise ornithine transcarbamylase (OTC) or methylmalonyl-CoA mutase (MUT1).

The present disclosure provides a modified human OTC protein having improved properties for the treatment of OTC deficiency in a patient. Preferably, the protein of the disclosure is produced from a codon optimized mRNA suitable for administration to a patient suffering from OTC deficiency wherein upon administration of the mRNA to the patient, the protein of the disclosure is expressed in the patient in therapeutically effective amounts to treat OTC deficiency. The present disclosure also provides codon optimized mRNA sequences encoding wild type human OTC comprising a 5 UTR derived from a gene expressed by Arabidopsis thaliana for use in treating OTC deficiency in a patient.