PTK2B and Alzheimer disease: Two independent studies identified that DNA methylation at sites close to Ank1, Cdh23, Rhbdf2, and Rpl13 may be linked to AD pathology (De Jager et al., 2014; Lord and Cruchaga, 2014; Lunnon et al., 2014); except for Cdh23, these genes are strongly linked to the AD-associated gene Ptk2b. Advanced ageing is also associated with increased mitochondrial dysfunction and damage, which promotes neurodegeneration via the generation of reactive oxygen species (ROS) and the promotion of neuroinflammation.