NEURODEGENERATION AND AGING - ROLE OF THE 2ND-GENOME

The latest Health Report of the World Health Organization predicts a s ignificant increase in the age of human populations over the next two decades, In the developed world, at least 20% of the population will b e older than 65 years, This development together with the as yet unkno wn etiology of many neuro degenerative disorders has caused an increas ed interest in the biology and pathophysiology of mitochondria, Dysfun ction of mitochondria has been linked to both normal aging and neurode generative disorders, with the latter occurring much more frequently a t higher age, Specifically, genetic defects in mitochondria have been shown to accumulate during life, and certain mutations of mitochondria l genes have been implicated in the etiology of Parkinson's and Alzhei mer's diseases, In addition, a large number of new mitochondria diseas es have been identified following the first description of mitochondri al mutations 10 years ago, While there can be little doubt that DNA de fects of mitochondria play a role in aging, specific mutations of mito chondrial genes underlying Parkinson's or Alzheimer's diseases remain to be identified, There is evidence, however, that mutations of the mi tochondrial genome may increase the susceptibility to neurodegeneratio n. (C) 1998 Wiley-Liss, Inc.