The non-coding Air RNA is required for silencing autosomal imprinted genes

@article{Sleutels2002TheNA,
  title={The non-coding Air RNA is required for silencing autosomal imprinted genes},
  author={Frank Sleutels and Ronald Zwart and Denise P. Barlow},
  journal={Nature},
  year={2002},
  volume={415},
  pages={810-813}
}
In genomic imprinting, one of the two parental alleles of an autosomal gene is silenced epigenetically by a cis-acting mechanism. A bidirectional silencer for a 400-kilobase region that contains three imprinted, maternally expressed protein-coding genes (Igf2r/Slc22a2/Slc22a3) has been shown by targeted deletion to be located in a sequence of 3.7 kilobases, which also contains the promoter for the imprinted, paternally expressed non-coding Air RNA. Expression of Air is correlated with… 
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Control of imprinting at the Gnas cluster.
TLDR
Targeted deletion analysis is performed to test candidate regulatory regions within the Gnas complex and, unlike other imprinted domains, two major control regions have been identified.
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TLDR
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    Proceedings of the National Academy of Sciences of the United States of America
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TLDR
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