Vergeer, W.

globin expression locus deletion position mouse transgene level transcription region erythroid cells result effect globin genes number grosveld figure globin locus analysis control fragment erythroid globin gene expression probe heterochromatin gene expression globin gene chromatin liver cells liver copy number dependence genome dnase genes dev hybridization chromatin structure percentage restriction enzyme sensitivity structure position effect chromosomal position globin mrna sensitivity hypersensitive fraser stroubouli copy numbers transcript 1 copy chromosome plasmid control region integration element reduction wijgerde activity activation heterochromatic regions position effects 4 copies promoter mouse genome embo j adult line 72 acids res copy number transgene expression clonal subpopulation chromosomal 13.5 day regulation adult blood assay centromere pericentromeric formation restriction satellite