A SNF2 protein targets variable copy number repeats and thereby influences allele-specific expression. A SNF2 protein targets variable copy number repeats and thereby influences allele-specific expression

ATRX is an X-linked gene of the SWI/SNF family whose role in vivo is currently unknown. Mutations in ATRX cause syndromal mental retardation. ATRX binds to tandem repeat (TR) sequences both in heterochromatin (e.g. telomeres) and euchromatin. Genes associated with these TRs can be dysregulated when ATRX is mutated and the degree to which their expression changes is determined by the size of the TR, producing skewed allelic expression. This explains the nature of the affected genes, the variable phenotypes seen with identical ATRX mutations and also illustrates a new mechanism underlying variable penetrance. Many of the TRs in ATRX targets are G-rich and predicted to form non-B DNA structures (including G quadruplex) in vivo. We have shown that ATRX binds G quadruplex structures in vitro suggesting a mechanism by which ATRX may play a role in various nuclear processes and how this is perturbed when ATRX is mutated. Overall design: 4 Human Erythroblast, 1 HEP3B and 1 Fibroblast ChIP-ChIP Sample For ChIP-Seq: one human erythroblasts, one mouse ES, one human erythroblast reference Sample, and one mouse ES input reference Sample.