Review Article

Exp Neurobiol 2014; 23(4): 271-276

Published online December 31, 2014

© The Korean Society for Brain and Neural Sciences

Hypothesis: Somatic Mosaicism and Parkinson Disease

Han-Joon Kim and Beom S. Jeon*

Department of Neurology and Movement Disorder Center, Parkinson Study Group,
and Neuroscience Research Institute, College of Medicine, Seoul National University, Seoul, Korea

Correspondence to: *To whom correspondence should be addressed.
TEL: 82-2-2072-2876, FAX: 82-2-3672-7553

Received: August 22, 2014; Revised: September 29, 2014; Accepted: September 29, 2014


Mutations causing genetic disorders can occur during mitotic cell division after fertilization, which is called somatic mutations. This leads to somatic mosaicism, where two or more genetically distinct cells are present in one individual. Somatic mutations are the most well studied in cancer where it plays an important role and also have been associated with some neurodegenerative disorders. The study of somatic mosaicism in Parkinson disease (PD) is only in its infancy, and a case with somatic mutation has not yet been described. However, we can speculate that a somatic mutation affecting cells in the central nervous system including substantia nigra dopaminergic neurons could lead to the development of PD through the same pathomechanisms of genetic PD even in the absence of a germ-line mutation. Theoretically, a number of genes could be candidates for genetic analysis for the presence of somatic mosaicism. Among them, SNCA and PARK2 could be the best candidates to analyze. Because analyzing brain tissues in living patients is impossible, alternative tissues could be used to indicate the genetic status of the brain. Performance of the technology is another factor to consider when analyzing the tissues.

Keywords: somatic mutation, somatic mosaicism, genetics, Parkinson disease