Neuropsychiatric Disease and Treatment (Nov 2018)
Identification of a novel mutation in APP gene in a Thai subject with early-onset Alzheimer's disease
Abstract
Vo Van Giau,1,* Vorapun Senanarong,2,* Eva Bagyinszky,1 Chanin Limwongse,2 Seong Soo A An,1 SangYun Kim3 1Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, Seongnam, South Korea; 2Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; 3Department of Neurology, Seoul National University College of Medicine & Neurocognitive Behavior Center, Seoul National University Bundang Hospital, Seongnam, South Korea *These authors contributed equally to this work Introduction: Early-onset Alzheimer’s disease (AD) accounts for than less 1% of all AD cases, with large variation in the reported genetic contributions of known dementia genes. Mutations in the amyloid precursor protein (APP) gene were the first to be recognized as the cause of AD. Methods: Here, a male patient with probable early-onset AD at the age of 55 years from Thailand was investigated by next-generation sequencing. Results: A novel mutation in exon 14 of APP (c.1810C>T, p.V604M) was found. He initially illustrated the clinical manifestations of progressive nonfluent aphasia in 2011. However, he was finally diagnosed with AD presenting logopenic aphasia in 2013. The follow-up magnetic resonance imaging scan showed progression of hippocampal trophy compared with the initial image. A 3D protein structure model revealed that V604M exchange could result in significant changes in the APP protein due to the increased hydrophobicity of methionine in the helix, which could result in altering of the APP functions. Conclusion: Additional studies to characterize APP p.V604M are necessary to further understand the effects of this mutation. Keywords: APP, Alzheimer’s disease, Thailand, V604M
