Disorders characterized by expansion of an unstable nucleotide repeat account for a number of inherited neurological diseases. Here, we review examples of unstable repeat disorders that nicely illustrate three of the major pathogenic mechanisms associated with these diseases: loss of function typically by disrupting transcription of the mutated gene, RNA toxic gain of function, and protein toxic gain of function. In addition to providing insight into the mechanisms underlying these devastating neurological disorders, the study of these unstable microsatellite repeat disorders has provided insight into very basic aspects of neuroscience.
Bibliographical noteFunding Information:
The authors’ work in this area was supported by grants from the N.I.H. (NS022920 & NS045667, H.T.O.; HD020521 and HD024064, S.T.W.; NS051630 and HD024064, D.L.N.) Figures were drawn with assistance of J. Frisch.