Predicting preferential DNA vector insertion sites: implications for functional genomics and gene therapy

Table 1 Properties of nonviral integrating vectors proposed for gene therapy

	Properties
Vector system	Activity^a	Target preferences^b	Positive/negative attributes^c
Sleeping Beauty	Standard	TA sites, random	Highly tested/cargo capacity decreases efficiency
ΦC31	Lower	Pseudo-att sites	Highly tested/induces chromosomal mutations and rearrangements
piggyBac	Same	TTAA sites (genes)	Too new to evaluate/targets transcription units
Tol2	Higher	Unknown	Cured tyrosinemia type 1 in mice/may target genes, too new to evaluate
ΦBT1	Lower	Pseudo-att sites	Cured PKU in mice/too new to evaluate
Frog Prince	Same	TA sites	Too new to evaluate

^aActivity is given relative to Sleeping Beauty (SB) in HeLa cells or other cells in which SB has been tested. ^bTarget sites for phage integrases φC31 and φBT1 are not found in mammalian genomes; sequences with similarities to the phage attachment sites (att sites) are targets, but they vary with cell type. ^cEvaluation with respect to gene therapy: only SB and φC31 have been extensively tested; the others are too new to know positive and negative attributes. PKU, phenylketonuria.

ISSN: 1474-760X