Abstract: Targeting constructs and methods of using them are provided for differentiation-dependent modification of nucleic acid sequences in cells and in non-human animals. Targeting constructs comprising a promoter operably linked to a recombinase are provided, wherein the promoter drives transcription of the recombinase in an differentiated cell but not an undifferentiated cell. Promoters include Blimp1, Prm1, Gata6, Gata4, Igf2, Lhx2, Lhx5, and Pax3. Targeting constructs with a cassette flanked on both sides by recombinase sites can be removed using a recombinase gene operably linked to a 3?-UTR that comprises a recognition site for an miRNA that is transcribed in undifferentiated cells but not in differentiated cells. The constructs may be included in targeting vectors, and can be used to automatically modify or excise a selection cassette from an ES cell, a non-human embryo, or a non-human animal.

Abstract: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

Abstract: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

Abstract: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

Abstract: The invention provides stem cell derived beta-pancreatic cells and animal models of T2D in which cells have been grafted. The stem cells bear a mutated form of SLC30A8 conferring protection or susceptibility to T2D. The cells and animal models can be used for drug screening as well as to provide insights into the mechanism of T2D and potentially new therapeutic and diagnostic targets.

Abstract: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

Abstract: Targeting constructs and methods of using them are provided for differentiation-dependent modification of nucleic acid sequences in cells and in non-human animals. Targeting constructs comprising a promoter operably linked to a recombinase are provided, wherein the promoter drives transcription of the recombinase in an differentiated cell but not an undifferentiated cell. Promoters include Blimp1, Prm1, Gata6, Gata4, Igf2, Lhx2, Lhx5, and Pax3. Targeting constructs with a cassette flanked on both sides by recombinase sites can be removed using a recombinase gene operably linked to a 3?-UTR that comprises a recognition site for an miRNA that is transcribed in undifferentiated cells but not in differentiated cells. The constructs may be included in targeting vectors, and can be used to automatically modify or excise a selection cassette from an ES cell, a non-human embryo, or a non-human animal.

Abstract: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

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: Methods are provided herein for assembling at least two nucleic acids using a sequence specific nuclease agent (e.g., a gRNA-Cas complex) to create end sequences having complementarity and subsequently assembling the overlapping complementary sequences. The nuclease agent (e.g., a gRNA-Cas complex) can create double strand breaks in dsDNA in order to create overlapping end sequences or can create nicks on each strand to produce complementary overhanging end sequences. Assembly using the method described herein can assemble any nucleic acids having overlapping sequences or can use a joiner oligo to assemble sequences without complementary ends.

Abstract: Methods and compositions are provided for generating or maintaining human iPS cells in culture. Methods include the use of a low osmolality medium to make human iPS cells, or use of a low osmolality medium to maintain human iPS cells. Methods for making targeted genetic modification to human iPS cells cultured in low osmolality medium are also included. Compositions include human iPS cells cultured and maintained using the low osmolality medium defined herein.

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: A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

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: Targeting constructs and methods of using them are provided for differentiation-dependent modification of nucleic acid sequences in cells and in non-human animals. Targeting constructs comprising a promoter operably linked to a recombinase are provided, wherein the promoter drives transcription of the recombinase in an differentiated cell but not an undifferentiated cell. Promoters include Blimp1, Prm1, Gata6, Gata4, Igf2, Lhx2, Lhx5, and Pax3. Targeting constructs with a cassette flanked on both sides by recombinase sites can be removed using a recombinase gene operably linked to a 3?-UTR that comprises a recognition site for an miRNA that is transcribed in undifferentiated cells but not in differentiated cells. The constructs may be included in targeting vectors, and can be used to automatically modify or excise a selection cassette from an ES cell, a non-human embryo, or a non-human animal.

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: 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: Methods and compositions are provided for modifying one or more target loci in a cell. Such methods comprise providing a cell comprising a first polynucleotide encoding a first selection marker operably linked to a first promoter active in the cell, wherein the first polynucleotide further comprises a first recognition site for a first nuclease agent. A first nuclease agent is introduced into a cell, wherein the first nuclease agent induces a nick or double-strand break at the first recognition site. Further introduced into the cell is a first targeting vector comprising a first insert polynucleotide flanked by a first and a second homology arm that correspond to a first and a second target site located in sufficient proximity to the first recognition site. At least one cell is then identified comprising in its genome the first insert polynucleotide integrated at the target locus.

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 are provided herein for assembling at least two nucleic acids using a sequence specific nuclease agent (e.g., a gRNA-Cas complex) to create end sequences having complementarity and subsequently assembling the overlapping complementary sequences. The nuclease agent (e.g., a gRNA-Cas complex) can create double strand breaks in dsDNA in order to create overlapping end sequences or can create nicks on each strand to produce complementary overhanging end sequences. Assembly using the method described herein can assemble any nucleic acids having overlapping sequences or can use a joiner oligo to assemble sequences without complementary ends.