Familial Parkinson's disease: a hint to elucidate the mechanisms of nigral degeneration.
In the majority of patients with Parkinson's disease (PD), it is now clear that genetic factors contribute to the pathogenesis of PD, although the contribution of genetic and environmental factors remains to be elucidated. The contribution of genetic factors to the pathogenesis of PD is supported by the demonstration of the high concordance in twins, increased risk among relatives of PD patients in case control and family studies, and the existence of familial PD based on single gene defects. Recently, several genes have been mapped and identified in patients with familial PD (FPD). alpha-Synuclein is involved in a rare dominant form of familial PD with dopa responsive parkinsonian features and Lewy body positive pathology. In contrast, parkin is responsible for autosomal recessive form of earlyonset PD with Lewy body-negative pathology. This form is identified with world-wide distribution among patients with young-onset PD. Furthermore, ubiquitin carboxy terminal hydrolase L1 (UCHL1) gene is responsible for an autosomal dominant form of typical PD, although only a single family has so far been identified with a mutation of this gene. In addition, DJ-1 has been identified as a causative gene for PARK7, a recessive form of familial PD. Now, a total of five causative genes including NR4A2 have been identified, and others such as PARK3, -4, -6, -8, -9, -10 have been mapped as hereditary forms of familial PD. The presence of different loci or different causative genes indicates that PD is not a single entity but a highly heterogeneous disorder. However, the functions of causative genes may share a common pathway such as an ubiquitin-proteasome pathway. Thus, identification and elucidation of the causative genes should enhance our understanding of the pathogenesis of not only familial PD, but also sporadic PD.
Department of Neurology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo, 113-0033, Tokyo, Japan. nhattori@med.juntendo.ac.jp
Nobutaka
N
Hattori
Hirokazu
H
Kobayashi
Yasuko
Y
Sasaki-Hatano
Kenichi
K
Sato
Yoshikuni
Y
Mizuno
D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008875:Middle Aged; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics; D015513:Oncogene Proteins / Q000235:genetics; D020734:Parkinsonian Disorders / Q000235:genetics* / Q000473:pathology; D000071617:Protein Deglycase DJ-1; D013378:Substantia Nigra / Q000473:pathology; D051843:Synucleins; D044767:Ubiquitin-Protein Ligases / Q000235:genetics; D051844:alpha-Synuclein
D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D015513:Oncogene Proteins; C497604:SNCA protein, human; D051843:Synucleins; D051844:alpha-Synuclein; D044767:Ubiquitin-Protein Ligases; C111567:parkin protein; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1