Ataxin-2 as potential disease modifier in C9ORF72 expansion carriers

作者：Van Blitterswijk Marka; Mullen Bianca; Heckman Michael G; Baker Matthew C; DeJesus Hernandez Mariely; Brown Patricia H; Murray Melissa E; Hsiung Ging Yuek R; Stewart Heather; Karydas Anna M; Finger Elizabeth; Kertesz Andrew; Bigio Eileen H; Weintraub Sandra; Mesulam Marsel; Hatanpaa Kimmo J; White Charles L III; Neumann Manuela; Strong Michael J; Beach Thomas G; Wszolek Zbigniew K; Lippa Carol; Caselli Richard; Petrucelli Leonard; Josephs Keith A

来源：Neurobiology of Aging, 2014, 35(10): 2421.e13.

DOI：10.1016/j.neurobiolaging.2014.04.016

• C9ORF72
• Ataxin-2
• ATXN2
• Motor neuron disease
• Amyotrophic lateral sclerosis
• Frontotemporal dementia
• Disease modifier

Repeat expansions in chromosome 9 open reading frame 72 (C9ORF72) are an important cause of both motor neuron disease (MND) and frontotemporal dementia (FTD). Currently, little is known about factors that could account for the phenotypic heterogeneity detected in C9ORF72 expansion carriers. In this study, we investigated 4 genes that could represent genetic modifiers: ataxin-2 (ATXN2), non-imprinted in Prader-Willi/Angelman syndrome 1 (NIPA1), survival motor neuron 1 (SMN1), and survival motor neuron 2 (SMN2). Assessment of these genes, in a unique cohort of 331 C9ORF72 expansion carriers and 376 control subjects, revealed that intermediate repeat lengths in ATXN2 possibly act as disease modifier in C9ORF72 expansion carriers; no evidence was provided for a potential role of NIPA1, SMN1, or SMN2. The effects of intermediate ATXN2 repeats were most profound in probands with MND or FTD/MND (2.1% vs. 0% in control subjects, p = 0.013), whereas the frequency in probands with FTD was identical to control subjects. Though intermediate ATXN2 repeats were already known to be associated with MND risk, previous reports did not focus on individuals with clear pathogenic mutations, such as repeat expansions in C9ORF72. Based on our present findings, we postulate that intermediate ATXN2 repeat lengths may render C9ORF72 expansion carriers more susceptible to the development of MND; further studies are needed, however, to validate our findings.

• 出版日期2014-10
• 单位西北大学