Genomic imprinting gets complicated in adults

(Cell Press) While two copies of genes -- one from each parent -- is usually a good thing, for about a hundred genes, one copy -- either the mother's or the father's copy -- is silenced, a process known as genomic imprinting. This silencing was thought to be stable. But this silence doesn't last in certain cell types, finds a mouse study published Sept. 20 in Cell Reports.