ABCA7 Mutation in Behavioral Variant of Frontotemporal Dementia: a Case Report.

Introduction: Frontotemporal lobar degeneration (FTLD), a major cause of early-onset dementia, includes a heterogeneous group of neurodegenerative disorders with a strong genetic component. Mutations in MAPT, GRN, and C9orf72 are found in about 40% of patients with the behavioural variant (bvFTD). More recently, rarer pathogenic variants have been identified in other genes, such as ABCA7, initially linked to Alzheimer’s disease but increasingly implicated in other neurodegenerative conditions. Here we describe a specific variant which has not previously been reported in the literature. Case presentation: We report the case of a 42-year-old woman who presented with progressive behavioural changes and executive dysfunction, consistent with a bvFTD. A whole exome sequencing (WES) was conducted in a family trio revealed a heterozygous nonsense variant in the ABCA7 gene (c.5260C>T, p.Arg1754*). Conclusion: This case highlights supports the hypothesis of a ABCA7 loss-of-function (LOF) associated with early-onset bvFTD. It contributes to expand the genetic spectrum of frontotemporal dementia and underscores the importance of broad genetic testing.