Mitochondrial defects in neurodegenerative disease

Over the past 12 years, a wide variety of neurodegenerative diseases has be en linked to mutations in mitochondrial genes located in either the mitocho ndrial DNA (mtDNA) or the nuclear DNA (nDNA). These disorders encompass an array of unorthodox inheritance patterns and a plethora of symptoms ranging from lethal neonatal multi-symptom disorders to later onset myopathies, ca rdiomyopathies, movement disorders, and dementias. The bases for the geneti c and phenotypic variability of mitochondrial diseases lie in the multiplic ity of the mitochondria genes dispersed across the human genome and the var iety of cellular pathways and functions in which the mitochondria play a ce ntral role. (C) 2001 Wiley-Liss, Inc.