title: Attenuated spread of X-inactivation in an X;autosome translocation.
abstract: X inactivation in female mammals involves transcriptional silencing of an entire chromosome in response to a cis-acting noncoding RNA, the X inactive-specific transcript (Xist). Xist can also inactivate autosomal sequences, for example, in X;autosome translocations; but here, silencing appears to be relatively inefficient. This variation has been attributed to either attenuated spreading of Xist RNA at the onset of X inactivation or inefficient maintenance of autosomal silencing. Evidence to date has favored the latter. Here, we demonstrate attenuated spreading of Xist RNA at the onset of X inactivation in the T(X;4)37H X;autosome translocation. Our findings provide direct evidence that underlying chromosome/chromatin features can disrupt spreading of the primary inactivating signal.
authors: Developmental Epigenetics, Medical Research Council Clinical Sciences Center, Imperial College Faculty of Medicine, Hammersmith Hospital, DuCane Road, London W12 ONN, United Kingdom.
authors: Bilyana C
authors: BC
authors: Popova
authors: Takashi
authors: T
authors: Tada
authors: Nobuo
authors: N
authors: Takagi
authors: Neil
authors: N
authors: Brockdorff
authors: Tatyana B
authors: TB
authors: Nesterova