Expression data from CD34+ hematopoietic progenitor cells

Gene transfer vectors based on gamma-retroviruses target actively transcribing genes indicating that the cellular gene expression profile can be predictive of their integration pattern. Therefore, different culture conditions leading to different transcriptional activity may translate into differences in the profile of targeted genes in cells transduced with these vectors. Recent data from two gene therapy trials for SCID-X1 conducted in France and the UK suggested that small differences between in vitro stimulation conditions could explain the disparity in the frequency of common integrations sites observed in the two studies.

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