Abstract: BANF1, PPP2CA, and ANKLE2 were identified as genes that promote tau aggregation when disrupted. Improved tauopathy models such as cells, tissues, or animals having mutations in or inhibition of expression of BANF1 and/or PPP2CA and/or ANKLE2 are provided. Methods of using such improved tauopathy models for assessing therapeutic candidates for the treatment of a tauopathy, methods of making the improved tauopathy models, and methods of accelerating or exacerbating tau aggregation in a tauopathy model are also provided.

Abstract: Compositions and methods are provided for modifying a genomic locus of interest in a eukaryotic cell, a mammalian cell, a human cell or a non-human mammalian cell using a large targeting vector (LTVEC) comprising various endogenous or exogenous nucleic acid sequences as described herein. Further methods combine the use of the LTVEC with a CRISPR/Cas system. Compositions and methods for generating a genetically modified non-human animal comprising one or more targeted genetic modifications in their germline are also provided.

Abstract: Non-human animal cells and non-human animals comprising a humanized TTR locus comprising a beta-slip mutation and methods of using such non-human animal cells and non-human animals are provided. Non-human animal cells or non-human animals comprising a humanized TTR locus comprising a beta-slip mutation express a human transthyretin protein or a chimeric transthyretin protein, fragments of which are from human transthyretin. Methods are provided for using such non-human animals comprising a humanized TTR locus to assess in vivo efficacy of human-TTR-targeting reagents such as nuclease agents designed to target human TTR.

Abstract: BANF1, PPP2CA, and ANKLE2 were identified as genes that promote tau aggregation when disrupted. Improved tauopathy models such as cells, tissues, or animals having mutations in or inhibition of expression of BANF1 and/or PPP2CA and/or ANKLE2 are provided. Methods of using such improved tauopathy models for assessing therapeutic candidates for the treatment of a tauopathy, methods of making the improved tauopathy models, and methods of accelerating or exacerbating tau aggregation in a tauopathy model are also provided.

Abstract: Compositions and methods are provided for modifying a genomic locus of interest in a eukaryotic cell, a mammalian cell, a human cell or a non-human mammalian cell using a large targeting vector (LTVEC) comprising various endogenous or exogenous nucleic acid sequences as described herein. Further methods combine the use of the LTVEC with a CRISPR/Cas system. Compositions and methods for generating a genetically modified non-human animal comprising one or more targeted genetic modifications in their germline are also provided.

Abstract: Nuclease-mediated methods for expanding repeats already present at a genomic locus are provided. Non-human animal genomes, non-human animal cells, and non-human animals comprising a heterologous hexanucleotide repeat expansion sequence inserted at an endogenous C9orf72 locus and methods of making such non-human animal cells and non-human animals through nuclease-mediated repeat expansion are also provided. Methods of using the non-human animal cells or non-human animals to identify therapeutic candidates that may be used to prevent, delay or treat one or more neurodegenerative disorders associated with repeat expansion at the C9orf72 locus are also provided.

Abstract: Compositions and methods are provided for creating and promoting biallelic targeted modifications to genomes within cells and for producing non-human animals comprising the modified genomes. Also provided are compositions and methods for modifying a genome within a cell that is heterozygous for an allele to become homozygous for that allele. The methods make use of Cas proteins and two or more guide RNAs that target different locations within the same genomic target locus. Also provided are methods of identifying cells with modified genomes.

Abstract: Compositions and methods are provided for creating and promoting biallelic targeted modifications to genomes within cells and for producing non-human animals comprising the modified genomes. Also provided are compositions and methods for modifying a genome within a cell that is heterozygous for an allele to become homozygous for that allele. The methods make use of Cas proteins and two or more guide RNAs that target different locations within the same genomic target locus. Also provided are methods of identifying cells with modified genomes.

Abstract: Nuclease-mediated methods for expanding repeats already present at a genomic locus are provided. Non-human animal genomes, non-human animal cells, and non-human animals comprising a heterologous hexanucleotide repeat expansion sequence inserted at an endogenous C9orf72 locus and methods of making such non-human animal cells and non-human animals through nuclease-mediated repeat expansion are also provided. Methods of using the non-human animal cells or non-human animals to identify therapeutic candidates that may be used to prevent, delay or treat one or more neurodegenerative disorders associated with repeat expansion at the C9orf72 locus are also provided.

Abstract: Genetically modified non-human animals are provided that exhibit a functional lack of one or more IncRNAs. Methods and compositions for disrupting, deleting, and/or replacing IncRNA-encoding sequences are provided. Genetically modified mice that age prematurely are provided. Also provided are cells, tissues and embryos that are genetically modified to comprise a loss-of-function of one or more IncRNAs.

Abstract: The disclosure relates to double stranded ribonucleic acid (dsRNAi) agents and compositions targeting a human chromosome 9 open reading frame 72 (C9orf72) gene, as well as methods of inhibiting expression of a C9orf72 gene and methods of treating subjects having a C9orf72-associated disease or disorder, e.g., C9orf72 amyotrophic lateral sclerosis/frontotemporal dementia or Huntington-Like Syndrome Due To C9orf72 Expansions, using such dsRNAi agents and compositions.

Abstract: Non-human animal genomes, non-human animal cells, and non-human animals comprising a humanized TTR locus and methods of using such non-human animal genomes, non-human animal cells, and non-human animals are provided. Non-human animal cells or non-human animals comprising a humanized TTR locus express a human transthyretin protein or a chimeric transthyretin protein, fragments of which are from human transthyretin. Methods are provided for using such non-human animals comprising a humanized TTR locus to assess in vivo efficacy of human-TTR-targeting reagents such as nuclease agents designed to target human TTR. Methods are also provided for making such non-human animals comprising a humanized TTR locus.

Abstract: Genetically modified non-human animals are provided that exhibit a functional lack of one or more lncRNAs. Methods and compositions for disrupting, deleting, and/or replacing lncRNA-encoding sequences are provided. Genetically modified mice that age prematurely are provided. Also provided are cells, tissues and embryos that are genetically modified to comprise a loss-of-function of one or more lncRNAs.

Abstract: Methods and compositions are provided for generating antigen-binding proteins against a foreign antigen of interest.

Abstract: Methods and compositions are provided for assessing CRISPR/Cas-mediated non-homologous end joining (NHEJ) activity and/or CRISPR/Cas-induced recombination of a target genomic locus with an exogenous donor nucleic acid in vivo or ex vivo. The methods and compositions employ non-human animals comprising a CRISPR reporter such as a genomically integrated CRISPR reporter for detecting and measuring targeted excision of a sequence between two CRISPR/Cas nuclease cleavage sites or disruption of a sequence near a CRISPR/Cas nuclease cleavage site and/or measuring CRISPR/Cas-induced recombination of the CRISPR reporter with an exogenous donor nucleic acid to convert the coding sequence for a first reporter protein to the coding sequence for a different second reporter protein. Methods and compositions are also provided for making and using these non-human animals.

Abstract: Methods and compositions are provided for assessing CRISPR/Cas-mediated non-homologous end joining (NHEJ) activity and/or CRISPR/Cas-induced recombination of a target genomic locus with an exogenous donor nucleic acid in vivo or ex vivo. The methods and compositions employ non-human animals comprising a CRISPR reporter such as a genomically integrated CRISPR reporter for detecting and measuring targeted excision of a sequence between two CRISPR/Cas nuclease cleavage sites or disruption of a sequence near a CRISPR/Cas nuclease cleavage site and/or measuring CRISPR/Cas-induced recombination of the CRISPR reporter with an exogenous donor nucleic acid to convert the coding sequence for a first reporter protein to the coding sequence for a different second reporter protein. Methods and compositions are also provided for making and using these non-human animals.

Abstract: Compositions and methods are provided for making rat pluripotent and totipotent cells, including rat embryonic stem (ES) cells. Compositions and methods for improving efficiency or frequency of germline transmission of genetic modifications in rats are provided. Such methods and compositions comprise an in vitro culture comprising a feeder cell layer and a population of rat ES cells or a rat ES cell line, wherein the in vitro culture conditions maintain pluripotency of the ES cell and comprises a media having mouse leukemia inhibitory factor (LIF) or an active variant or fragment thereof. Various methods of establishing such rat ES cell lines are further provided. Methods of selecting genetically modified rat ES cells are also provided, along with various methods to generate a transgenic rat from the genetically modified rat ES cells provided herein. Various kits and articles of manufacture are further provided.

Abstract: Methods and compositions are provided for generating F0 fertile XY female animals. The methods and compositions involve making XY pluripotent or totipotent animal cells, in vitro cell cultures, or embryos that are capable of producing a fertile female XY animal in an F0 generation. Such cells, embryos, and animals can be made by silencing a region of the Y chromosome. Optionally, the cells can also be cultured in feminizing medium such as a low-osmolality medium and/or can be modified to decrease the level and/or activity of an Sry protein. Methods and compositions are also provided for silencing a region of the Y chromosome in an XY pluripotent or totipotent animal cell, or in vitro cell cultures, embryos, or animals derived therefrom, by maintaining an XY pluripotent or totipotent animal cell in a feminizing medium.

Abstract: Methods and compositions are provided for generating targeted genetic modifications on the Y chromosome or a challenging target locus. Compositions include an in vitro culture comprising an XY pluripotent and/or totipotent animal cell (i.e., XY ES cells or XY iPS cells) having a modification that decreases the level and/or activity of an Sry protein; and, culturing these cells in a medium that promotes development of XY F0 fertile females. Such compositions find use in various methods for making a fertile female XY non-human mammal in an F0 generation.

Abstract: Methods and compositions are provided for generating F0 fertile XY female animals. The methods and compositions involve making XY pluripotent or totipotent animal cells, in vitro cell cultures, or embryos that are capable of producing a fertile female XY animal in an F0 generation. Such cells, embryos, and animals can be made by silencing a region of the Y chromosome. Optionally, the cells can also be cultured in feminizing medium such as a low-osmolality medium and/or can be modified to decrease the level and/or activity of an Sry protein. Methods and compositions are also provided for silencing a region of the Y chromosome in an XY pluripotent or totipotent animal cell, or in vitro cell cultures, embryos, or animals derived therefrom, by maintaining an XY pluripotent or totipotent animal cell in a feminizing medium.