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Impact of Neurogenomics on the Development
of Personalized Neurology
Genomics is improving our understanding of neurologic diseases. This will be an
important basis for the development of rational therapies in integrated healthcare of
the future. Genomics will have the following impact on healthcare:
- Increase in the range of diseases that can be treated with drugs.
- Increase in the precision and effectiveness of drugs. If a patient can be diagnosed
in terms of DNA mutations, alleles, or polymorphisms pertaining to a specifi c
disease, their response to treatment can be vastly improved. - An increase in the ability to anticipate diseases rather than just reacting to them.
This may enable the institution of preventive measures. - Development of more effective drugs may lead to a trend for treatment with
drugs rather than surgery.
With the sequencing of the genome and genetic redefi nition of neurologic dis-
eases, pathomechanism will be better understood and will facilitate early detection
by molecular methods and effective strategies for management. Availability of low-
cost genomic sequencing will expand the use of genomic information in the practice
of neurology. Drugs will be targeted better to diseases in particular patients based
on genotype information. Toxicity will be predictable in most cases prior to drug
administration. These will be signifi cant contributions to personalized neurology.
Epigenomics/Epigenetics
The epigenome is a record of the chemical changes to the DNA and histone proteins
of an organism, which can be inherited by an organism’s offspring. The epigenome
is involved in regulation of gene expression, development, and tissue differentia-
tion. Unlike the underlying the genome which is largely static within an individual,
the epigenome can be altered by environmental conditions. Changes in the
epigenome can result in changes in function of the genome.
Epigenetics refers to the study of changes in the regulation of gene activity and
expression that are not dependent on gene DNA sequence. Whereas epigenetics
often refers to the study of single genes or sets of genes, epigenomics refers to more
global analyses of epigenetic changes across the entire genome.
Neurological disorder are not only associated with genomic mutations and tran-
scriptomic dysregulations, but with changes in the epigenome. Among the various
types of epigenomic modifi cations, DNA methylation, histone modifi cations and
expression levels of microRNAs (miRNAs) have been the most widely studied.
DNA methylation is implicated in the development of human brain as well as plas-
ticity underlying learning and memory. Widespread reconfi guration occurs in the
methylome and the conserved non-CG methylation accumulates in the neuronal
genome during development (Lister et al. 2013 ).
12 Personalized Management of Neurological Disorders