Gene expression changes underlying cortical pathology: clues to understanding neurological disability in multiple sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with an unknown etiology. The clinical disease course is variable, with the majority of patients experiencing reversible episodes of neurological disability in the third or fourth decade of life, eventually followed by a state of irreversible progression. Continuous axonal and neuronal loss is thought to be the major cause of this progression. Over the last decade, extensive research has targeted the gray matter and its role in MS pathogenesis. While pathological and imaging studies have begun to reveal important clues about the role of cortical pathology, gene expression studies in MS cortex are still emerging. Microarray-based comparative gene expression profiling provides a snapshot of genes underlying a particular condition and has been performed using brain tissues from patients with progressive MS. In this review, we summarize existing data from gene expression changes in cortical tissues from MS brains and how they may provide clues to the pathogenesis.