title: Mechanism of random integration of foreign DNA in transgenic mice.
abstract: Little is known about how foreign DNA is randomly integrated into chromosomes in transgenic animals. In the current study, the insertion sites of 36 transgenic mice were mapped by thermal asymmetric interlaced PCR, and 38 junction sequences were obtained from 30 samples. Analysis of the 38 sequences revealed that 44.7 % of integration events occurred within host gene regions, including 13.2 % (5/38) in exonic regions and 31.6 % (12/38) in intronic regions. The results also revealed that all non-end side integrations of foreign DNA were mediated by short sequence homologies (microhomologies) and that the end side integrations occurred in the presence or absence of microhomologies. In addition, microhomology-mediated mechanisms were also confirmed in four transgenic Arabidopsis thaliana lines. The results indicate that foreign DNA is easily integrated into host gene regions. These results also suggest that the integration of both ends of foreign DNA follows the above-mentioned mechanism in many transgenic/transformed organisms.
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Bo-Wen
authors.initials: BW
authors.lastname: Yan
authors.forename: Yao-Feng
authors.initials: YF
authors.lastname: Zhao
authors.forename: Wen-Guang
authors.initials: WG
authors.lastname: Cao
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Ke-Mian
authors.initials: KM
authors.lastname: Gou
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000235:genetics*; D001483:Base Sequence; D015139:Blotting, Southern; D017931:DNA Primers / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic / Q000235:genetics*; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified / Q000235:genetics*; D016133:Polymerase Chain Reaction; D060888:Real-Time Polymerase Chain Reaction; D014170:Transformation, Genetic / Q000235:genetics*; D019076:Transgenes / Q000235:genetics*
chemical_list: D017931:DNA Primers