Antisense RNA in imprinting: spreading silence through Air.

In some animals, including mammals, a number of genes are expressed differently according to whether they have been inherited from the mother or from the father, through a process known as genomic imprinting. Noncoding RNAs have increasingly been found associated with imprinted genes, but their role, if any, has remained enigmatic. A recent study provides the first evidence that, at least in one case, a noncoding RNA has a direct role in regulating imprinted gene expression in cis.