--to cause neuropathy, though.

MGUS is definitely a cause of neuropathy, and often at lower levels than would be a concern for blood cancers--there is often antibody cross reactivity to components of peripheral nerve.

See:

http://neuromuscular.wustl.edu/antibody/mprotein.htm

http://www.neuropathy.org/site/DocSe...pdf?docID=1061