Abstract: An I-CreI variant, wherein at least one of the two I-CreI monomers has at least two substitutions, one in each of the two functional subdomains of the LAGLIDADG core domain situated respectively from positions 26 to 40 and 44 to 77 of I-CreI, said variant being able to cleave a DNA target sequence from the human IL2RG gene. Use of said variant and derived products for the prevention and the treatment of X-linked severe combined immunodeficiency.

Abstract: An I-CreI variant, wherein one of the two I-CreI monomers has at least two substitutions, one in each of the two functional subdomains of the LAGLIDADG (SEQ ID NO: 150) core domain situated respectively from positions 26 to 40 and 44 to 77 of I-CreI, said variant being able to cleave a DNA target sequence from the mouse ROSA26 locus. Use of said variant and derived products for the engineering of transgenic mice and recombinant mouse cell lines expressing an heterologous protein of interest.

Abstract: A single chain homing endonuclease, comprising a first variant of I-CreI having the amino acid sequence of accession number pdb 1g9y (SEQ ID NO: 23 is residues 1-153 of pdb Ig9y) and a second variant of I-CreI variant having the amino acid sequence of accession number pdb 1g9y (SEQ ID NO: 23 is residues 1-153 of pdb Ig9y) in a single polypeptide.

Abstract: A method for enhancing the cleavage activity of an I-CreI derived meganuclease, comprising the site-specific mutation of at least one amino acid residue which is selected in the group consisting of: the glycine at position 19, the phenylalanine at position 54, the phenylalanine at position 87, the serine at position 79, the valine at position 105 and the isoleucine at position 132 of I-CreI, and its application for the manufacturing of meganuclease cleaving a DNA target of interest, for use in genome therapy (treatment of genetic diseases) and genome engineering (making of transgenic animals, transgenic plants and recombinant cell lines).

Abstract: A single chain homing endonuclease, comprising a first variant of I-CreI having the amino acid sequence of accession number pdb 1g9y and a second variant of I-CreI variant having the amino acid sequence of accession number pdb 1g9y in a single polypeptide.

Abstract: An I-CreI variant or a single-chain derivative having at least one substitution in one of the two functional subdomains of the LAGLIDADG (SEQ ID NO: 153) core domain situated from positions 26 to 40 and 44 to 77 of I-CreI, and being able to cleave a DNA target sequence from the HPRT gene having a nucleotide sequence of SEQ ID NO: 1 to 14. Use of said variant for inducing a site-specific modification in the HPRT gene, for therapeutic (gene therapy of Lesch-Nyhan syndrome) or non-therapeutic purpose (engineering of transgenic animals and recombinant cell lines).

Abstract: New rare-cutting endonucleases, also called custom-made meganucleases, which recognize and cleave a specific nucleotide sequence, derived polynucleotide sequences, recombinant vector cell, animal, or plant comprising said polynucleotide sequences, process for producing said rare-cutting endonucleases and any use thereof, more particularly, for genetic engineering, antiviral therapy and gene therapy.

Abstract: Use of meganucleases for inducing homologous recombination ex vivo and in toto in vertebrate somatic tissues and to its application for genome engineering and gene therapy.