» Articles » PMID: 28010125

Proposed Association Between the Hexanucleotide Repeat of C9orf72 and Opposability Index of the Thumb

Overview
Specialty Neurology
Date 2016 Dec 25
PMID 28010125
Citations 1
Authors
Affiliations
Soon will be listed here.
Abstract

Objective: Amyotrophic lateral sclerosis (ALS) is a fatal disease caused by motor neuron and sub-cerebral projection neuron degeneration. We sought to explore the particular susceptibility of humans to neurodegeneration and whether any characteristic human features might predispose to selective vulnerability of the critical motor circuitry in ALS. The pathophysiology of the C9orf72 repeat is not yet understood, despite its role as a common cause of ALS and frontotemporal dementia.

Methods: We examined the development of the monosynaptic cortico-motoneuronal system, key to skilled hand movements, measured by the thumb opposability index, and its relationship to the C9orf72 hexanucleotide repeat expansion, a strong predisposing factor for neurodegeneration, using the genomic tool BLAST.

Results: We found a statistically significant linear relationship between the C9orf72 hexanucleotide bit score, a measure of genomic conservation of the aligned region across different species, and the thumb opposability index (Pearson's correlation coefficient of 0.78, p value 0.023). The C9orf72 hexanucleotide repeat was only found in humans, chimpanzees and gorillas, species with higher opposability indices.

Conclusions: This may support a role of the hexanucleotide repeat in the same developmental pathways in species with higher prehensility, which may be associated with the selective vulnerability of cortico-motoneuronal cells in humans, manifested most obviously as the 'split hand' syndrome in ALS.

Citing Articles

Autophagy Dysfunction in ALS: from Transport to Protein Degradation.

Cozzi M, Ferrari V J Mol Neurosci. 2022; 72(7):1456-1481.

PMID: 35708843 PMC: 9293831. DOI: 10.1007/s12031-022-02029-3.

References
1.
Fowler C, Griffiths D, de Groat W . The neural control of micturition. Nat Rev Neurosci. 2008; 9(6):453-66. PMC: 2897743. DOI: 10.1038/nrn2401. View

2.
Jara J, Genc B, Cox G, Bohn M, Roos R, Macklis J . Corticospinal Motor Neurons Are Susceptible to Increased ER Stress and Display Profound Degeneration in the Absence of UCHL1 Function. Cereb Cortex. 2015; 25(11):4259-72. PMC: 4626833. DOI: 10.1093/cercor/bhu318. View

3.
Waterhouse A, Procter J, Martin D, Clamp M, Barton G . Jalview Version 2--a multiple sequence alignment editor and analysis workbench. Bioinformatics. 2009; 25(9):1189-91. PMC: 2672624. DOI: 10.1093/bioinformatics/btp033. View

4.
Smith B, Newhouse S, Shatunov A, Vance C, Topp S, Johnson L . The C9ORF72 expansion mutation is a common cause of ALS+/-FTD in Europe and has a single founder. Eur J Hum Genet. 2012; 21(1):102-8. PMC: 3522204. DOI: 10.1038/ejhg.2012.98. View

5.
Rathelot J, Strick P . Subdivisions of primary motor cortex based on cortico-motoneuronal cells. Proc Natl Acad Sci U S A. 2009; 106(3):918-23. PMC: 2621250. DOI: 10.1073/pnas.0808362106. View