(From ScienceDaily). Age-related neurodegenerative diseases are failure modes of an exceedingly complex machine - so it shouldn't be surprising to find that many different mechanisms contribute to the sad end result: "[The gene] KCNC3 forms a potassium channel, part of a biochemical mechanism that regulates the electrical impulses of bursting neurons. Although potassium channel mutations have previously been linked to episodic disorders such as seizures, this is the first time they have been identified as causative factors - and potentially therapeutic targets - in neurodegenerative diseases. ... This is the first time neurodegeneration has been directly linked to potassium channel mutations."
Link: http://www.sciencedaily.com/releases/2006/02/060228084852.htm