Change in cognitive functioning over 10 years was associated with DNA methylation levels in AGBL4 (p = 9.01 × 10−7) and SORBS1 (p = 5.28 × 10−6), with the first gene playing an important role in neuronal survival and the latter gene implicated before in Alzheimer's disease and ischemic stroke. The gene discussed is AGBL4; the disease is early-onset autosomal dominant Alzheimer disease.