Provided herein are compositions and methods of using base editors comprising a polynucleotide programmable nucleotide binding domain and a nucleobase editing domain in conjunction with a guide polynucleotide. Also provided herein are base editor systems for editing nucleobases of target nucleotide sequences.

The disclosure provides methods of deaminating adenosine and cytosine bases in a target nucleic acid sequence in an USH2A gene comprising contacting the USH2A gene with a base editor in association with a guide RNA (gRNA). In some aspects, base editing is used to restore US2HA function by disrupting a splice site in the USH2A gene sequence to induce skipping of an exon containing a mutation, while in other embodiments, base editing is used to restore US2HA function by correcting a point mutation e.g., in an exon) so as to correct mutations. The disclosure also provides complexes of adenosine base editors and guide RNAs, and complexes of cytidine base editors and guide RNAs. The disclosure further provides pharmaceutical compositions and cells comprising these complexes. The disclosure also provides vectors encoding these complexes, base editors, and gRNAs. In some embodiments, the methods and compositions provided herein are used to treat Usher syndrome and autosomal recessive retinitis pigmentosa (arRP).

The present disclosure relates to nucleobase editors and methods of use thereof. Disclosed herein are fusion proteins, systems, and compositions for editing disease-associated mutations and methods of use thereof. In some aspects, disclosed herein is a fusion protein comprising a Cas9 nickase and a nucleotide deaminase, wherein the Cas9 nickase comprises a first amino acid substitution at a position selected from the group consisting of 262, 324, 409, 480, 543, 694, and 1219 when compared to SEQ ID NO: 11, and wherein the Cas9 nickase comprises a second amino acid substitution at a position selected from the group consisting of 1111, 1135, 1218, 1219, 1322, 1335, and 1337 when compared to SEQ ID NO: 11.

The invention features compositions and methods for introducing mutations into the hepatitis B virus (HBV) genome.

The invention features novel programmable nucleobase editors comprising adenosine deaminase domains and methods of using the same for polynucleotide editing. In some embodiments, programmable nucleobase editors edit a pathogenic mutation associated with a genetic disease.

Compositions and methods for small molecule control of precise base editing are disclosed.

The present disclosure provides improved adenosine base editors (ABE) that have an expanded range of PAM sequence recognition capability (i.e., recognition of non-canonical ′5-NGG-′3 PAM sequence). In addition, the present disclosure provides improved cytidine base editors (CBE) and adenosine base editors (ABE) comprising circular permutant variants of Cas9 (CP-Cas9) with an increased window of base editing within the protospacer sequence (e.g., from about 4-5 nucleotides to up to about 8-9 nucleotides) and even outside of the protospacer sequence.

Aspects of the disclosure relate to compositions, nucleic acids, vectors, viruses, and methods useful for treating hearing loss and/or blindness, for example, Usher Syndrome type IF. The present disclosure provides isolated nucleic acids, vectors, and rAAV.9.PHP.B comprising a transgene encoding a mini-PCDH15, and methods of treating hearing loss using the same. The present disclosure also provides a gRNA associated with a base editor to correct one or more mutations in PCDH15 for treating hearing loss and/or vision loss.

The disclosure provides for systems, methods, and compositions for targeting and editing nucleic acids. In particular, the invention provides non-naturally occurring or engineered RNA-targeting systems comprising a RNA-targeting Cas13 protein, at least one guide molecule, and at least one adenosine deaminase protein or catalytic domain thereof.

The present disclosure provides a fusion polypeptide comprising: a) an enzymatically active RNA-guided endonuclease that introduces a single-stranded break in a target DNA; and b) an error-prone DNA polymerase. The present disclosure provides a system comprising: a) a fusion polypeptide of the present disclosure; and b) a guide RNA. The present disclosure provides a cell comprising a fusion polypeptide of the present disclosure, or a system of the present disclosure. The present disclosure provides a method of mutagenizing a target polynucleotide.