Increased hexanucleotide expansion in the c9orf72 gene on chromosome 9p21 has radically altered the understaning of ALS and FTD pathogenesis.  In the case of ALS, it has convincigly elevtaed the disorder to a central level, suggetsing the importance of frontal cortical dysufnction in ALS.  In addition, the understanding of FTD symtomatology, and how it related to undelrying pathology, has also been advanced.

In an upcoming issue of JNNP (http://jnnp.bmj.com/content/early/2014/02/12/jnnp-2013-306995.full), Downey and collegaues report on a novel clinical feature in FTD.  While it is well recognised that psychiatric symtoms are a distinguishing feature of c9orf72 FTD,  the concepot of altered body schema processing has been suggested but not previousy systematically assessed in FTD.  Downey and colleagues established deficits in somatosensory body schema processing, (i.e. tactile discrimination, proprioception, body part illusions and self vs non-self differentiation).  Such deficits could form the pathophysiological basis for the “beahvioural” and “psychiatric” issues  evident in c9orf72 FTD, and link this with anatomical disruption of corticla-subcortical networks.

Read more at:    http://jnnp.bmj.com/content/early/2014/02/12/jnnp-2013-306995.full

• Research paper