Newborns whose mothers suffered from depression while they were pregnant are known to have more highly methylated glucocorticoid-receptor genes than others.
They found that women abused during pregnancy were significantly more likely than others to have a child with methylated glucocorticoid-receptor genes.
Translocations can disrupt SNRNP and move the small nucleolar RNA genes away from their imprinting center, causing them to get methylated and turned off.
If the paternal imprinting center is mutated, the region gets methylated and those genes get turned off, meaning that both the maternal and paternal genes are silenced.
In one famous experiment, when mother rats weren't attentive enough to their pups, genes in the babies that helped them manage stress were methylated and turned off.
If both copies of chromosome 15 were derived from the mother, that means all the prader willi genes are methylated and silenced, since there's no unsilenced paternal genes.