H19 and Alzheimer disease: Because changes in IGF2 levels in the CNS and peripheral tissues have been associated with age-related cognitive decline and AD pathology in humans and mouse models72, we first measured IGF2 levels, Igf2 expression, H19 ICR methylation, CTCF binding, and histone modification in the cerebrum, liver, and blood plasma of 6- and 12-month-old, male and female 5xFAD and WT mice.