. 2015 Nov 27;16(1):46–56. doi: 10.1093/bfgp/elv053

Table 1.

Examples of HDR-mediated gene modification in mammalian zygotes

Subject	Gene modification	Efficiency in neonates (embryos)	Off-target mutation	Mosaicism	Genome editing	Remarks	Reference
Mouse zygotes	Introduction of V5 tag (42bp) into Sox2, two loxP (34 bp) sites into Mecp2	Sox: 6.0%, Mecp2: 0.8%	Yes (Mecp2)	Yes	Cas9	Cytoplasmic or pronuclear injection	[39]
Mouse zygotes	Correction of Crytg with 1bp deletion in exon3	4.4∼5.7%	Yes	N.D.	Cas9	Cytoplasmic injection	[40]
Mouse zygotes	Correction of Dmd^mdx	9.1%	(No)^a	Yes	Cas9	Pronuclear injection only, or pronuclear and cytoplasmic injections	[41]
Mouse zygotes	Correction of Crb1^rd⁸	27%	Yes	Yes	TALEN	Pronuclear injection	[42]
Rat zygotes	Correction of Tyr^c, Asip^a, Kit ^h	Tyr: 7.7 %, Asip:18.2%, Kit: 4.0%	(No)^a	Yes	Cas9	Pronuclear injection	[43]
Human zygotes	Introduction of silent mutations into HBB	(4.7%)	Yes	Yes	Cas9	Cytoplasmic injection	[24]

(No) shows that no off-target mutations were identified at potential off-target sites.