A microorganism is transformed to be capable of producing guanidinoacetic acid (GAA). A method can be used for the fermentative production of GAA using such a microorganism. A corresponding method can be used for the fermentative production of creatine.

Methods of assessing the efficacy of an agent in treating a disease or disorder are provided that include determining whether the agent causes, or inhibits, direct or indirect recruitment and/or ubiquitination and/or degradation of argininosuccinate synthetase 1 (ASS1).

Compositions and regimens useful in treating type I citrullenemia are provided. The compositions include recombinant adeno-associated virus (rAAV) with a transthyretin enhancer and promoter driving expression of a human Argininosuccinate Synthase 1 (ASS1).

Provided herein are methods for facilitating or inducing stable transgene integration and expression in a proliferating cell, comprising administering to the cell (i) a recombinant AAV (rAAV) vector comprising the transgene flanked by transposon-derived inverted terminal repeat sequences, which sequences are in turn flanked by AAV-derived inverted terminal repeat regions, and (ii) a source of a transposase that recognises said transposon-derived inverted terminal repeat sequences and directs the genomic integration of the transgene into the genome of the proliferating cell. Also provided are methods and transgene delivery systems for the treatment or prevention of diseases affecting, associated with or characterised by proliferating cells, including paediatric liver diseases, bone marrow diseases and cancer.

Provided herein are methods for facilitating or inducing stable transgene integration and expression in a proliferating cell, comprising administering to the cell (i) a recombinant AAV (rAAV) vector comprising the transgene flanked by transposon-derived inverted terminal repeat sequences, which sequences are in turn flanked by AAV-derived inverted terminal repeat regions, and (ii) a source of a transposase that recognises said transposon-derived inverted terminal repeat sequences and directs the genomic integration of the transgene into the genome of the proliferating cell. Also provide are methods and transgene delivery systems for the treatment or prevention of diseases affecting, associated with or characterised by proliferating cells.

The present invention relates to methods and compositions for editing an ASS1 polynucleotide, e.g., an ASS1 polynucleotide comprising a SNP associated with Citrullinemia Type 1. The invention also relates to methods and compositions for treating or preventing Citrullinemia Type 1 in a subject.

The present invention provides, among other things, methods of treating Argininosuccinate Synthetase Deficiency (ASD), including administering to a subject in need of treatment a composition comprising an mRNA encoding argininosuccinate synthetase (ASS1) at an effective dose and an administration interval such that at least one symptom or feature of ASD is reduced in intensity, severity, or frequency or has delayed in onset. In some embodiments, the mRNA is encapsulated in a liposome comprising one or more cationic lipids, one or more non-cationic lipids, one or more cholesterol-based lipids and one or more PEG-modified lipids.

Compositions and regimens useful in treating type I citrullenemia are provided. The compositions include recombinant adeno-associated virus (rAAV) with a transthyretin enhancer and promoter driving expression of a human Argininosuccinate Synthase 1 (ASS1).

The present invention provides, among other things, methods of treating Argininosuccinate Synthetase Deficiency (ASD), including administering to a subject in need of treatment a composition comprising an mRNA encoding argininosuccinate synthetase (ASS1) at an effective dose and an administration interval such that at least one symptom or feature of ASD is reduced in intensity, severity, or frequency or has delayed in onset. In some embodiments, the mRNA is encapsulated in a liposome comprising one or more cationic lipids, one or more non-cationic lipids, one or more cholesterol-based lipids and one or more PEG-modified lipids

A field of gene therapy and engineering of viral vectors for use in gene therapy. More specifically, it is disclosed herein adeno-associated virus vectors and expression cassettes comprising S/MAR sequences of c-Myc or IFN-β for the treatment of liver diseases, notably in neonates.