Table.

Endonuclease-mediated gene editing in immunodeficient NSG/NRG mice

Mouse Strain	Year	Loci	Endonuclease1	Strategy	Efficiency2
NRG3	2012	Fah	ZFN	Knockout	up to 20%
NSG	2013	BAFF (BLyS), and other loci	TALEN	Knockout	up to 16%
NSG	2013	Hprt	CRISPR/Cas9	Knockout	up to 18%
NSG	2014	Multiple loci	CRISPR/Cas9	Knockout	14% – 85%
NSG	2015	Rhbdf2	CRISPR/Cas9	Knock-in (<100 bp insert)	up to 50%
NSG	2015	Multiple loci	CRISPR/Cas9	Knockout	13% – 81%
NSG	2015	Rosa26	CRISPR/Cas9	Knock-in (<100 bp insert)	up to 60%
NSG	2016	Multiple loci	CRISPR/Cas9	Knockout	7% – 50%

Note: A typical project consists of 100 microinjected zygotes yielding on average 22 live-born pups that are screened by PCR and Sanger sequencing for desired genetically modified events. The founder animals are backcrossed to the appropriate strain, and offspring are genotyped for the required events. Subsequently, heterozygous animals are bred to generate homozygous animals [for our detailed methodology see (Low et al., 2016)].

¹The high degree of variation in efficiency is linked to microinjection conditions and the targeting of different chromosomal loci.

²CRISPR/Cas9 endonuclease-mediated gene editing has significantly improved the targeting efficiency.

³NOD.Cg-Rag1^tm1Mom Il2rg^tm1Wjl/SzJ, also known as NOD-Rag1^null IL2rg^null, abbreviated as (NRG).