Rare missense variants in TREM2 and ABCA7 in a patient with sporadic early‐onset alzheimer's disease

Abstract

Alzheimer’s disease (AD) is a clinically heterogeneous neurodegenerative disease. Presentations of symptoms in individuals before the age of 65 years are classified as early-onset Alzheimer’s disease (EOAD). According to the family history, cases can be divided into early-onset familial AD (EOFAD) and sporadic (sEOAD). The latter are thought to be predominantly polygenic. The accumulation of variants which independently increase the risk of late-onset Alzheimer’s disease (LOAD) may lead to sEOAD at an earlier stage of life (Barber et al., 2017; Wingo et al., 2012). Here, we present an Argentine patient who began with memory deficits at the age of 49. Magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and neurocognitive testing results were compatible with a dementia of the Alzheimer type. Also, the patient did not have family history of the disease