Reprogramming of somatic cells to pluripotent cells promises to transform regenerative medicine. Recently many groups have achieved direct reprogramming of somatic cells by forced expression of defined factors using multiple viral vectors. However, such induced pluripotent stem (iPS) cells contain a number of viral vector integrations, any one of which could cause unpredictable genetic dysfunct...

BACKGROUND Circular forms of viral genomic DNA are generated during infection of cells with retroviruses like HIV-1. Such circles are unable to replicate and are eventually lost as a result of cell division, lending support to the prevalent notion that episomal retroviral DNA forms are dead-end products of reverse transcription. RESULTS We demonstrate that circular DNA generated during transd...

Reprogramming of somatic cells to pluripotent cells promises to transform regenerative medicine. Recently many groups have achieved direct reprogramming of somatic cells by forced expression of defined factors using multiple viral vectors. However, such induced pluripotent stem (iPS) cells contain a number of viral vector integrations, any one of which could cause unpredictable genetic dysfunct...

Reprogramming of somatic cells to pluripotent cells promises to transform regenerative medicine. Recently many groups have achieved direct reprogramming of somatic cells by forced expression of defined factors using multiple viral vectors. However, such induced pluripotent stem (iPS) cells contain a number of viral vector integrations, any one of which could cause unpredictable genetic dysfunct...