Screening for gene mutation in early onset Alzheimer’s disease and frontotemporal dementia: Report from a Serbian tertiary referral center

Abstract

AbstractBackgroundEarly‐onset dementia (EOD) is conventionally considered to include patients with disease onset before 65 years of age. Alzheimer’s disease (AD) and Frontotemporal dementia (FTD) are two most common forms of degenerative EOD. Our aim was to screen for known gene mutation status in consecutive degenerative EOD patients.MethodTwo hundred and eight consecutive patients diagnosed according to the current clinical criteria for AD and FTD spectrum were recruited from the Neurology Clinic, Clinical Centre of Serbia from 01.04.2012. until 01.04.2017. Patient from AD spectrum were tested for APP, PSEN1, GRN, MAPT and C9ORF72 gene mutation and FTD patients for GRN, MAPT, C9ORF72, VCP, ANG gene mutation.ResultGene mutations were identified in 3.9% of our AD patients: 2.3% patients had mutations in the PSEN1 gene and 1.5% patients in the APP gene. There was no MAPT, GRN and C9ORF72 mutations carriers in our AD cohort. Genetic mutations have been demonstrated in 10.3% of patients with FTD. The most frequent was the hexanucleotide expansion in C9ORF72 (6.4% of all FTD patients), following mutations in GRN, VCP and ANG with the same frequency of (1.3% FTD for each gene). No patient was a MAPT mutation carrier.ConclusionGene mutations were rare causes in our AD cohort. The frequency of carriers was higher in FTD patients‐ mutations were identified in C9ORF72, GRN, VCP and ANG genes. No MAPT mutation carriers were identified in our cohort of patients with degenerative EOD.