Mental Illnesses

In 2003, Dr. Moshe Szyf, professor of Pharmacology, McGill
University, and Michael Meaney, Associate Director of Research,
Douglas Hospital, conducted an important experiment.

First they observed that young rats who received a healthy
dose of maternal licking and grooming (the human equivalent of
maternal care) as pups developed into much calmer adults.  Those
rats who were deprived at the onset of this rat-like maternal
affection were decidedly more stressed.  This, needless to say,
is not an earth-shaking discovery.  We have known for a long time
the importance of maternal care, and its lifetime impact on the
individual.

The question raised by Meaney was “why the change in
behavior?”  It seems that the maternal licking stimulate a
chemical change in the glucocortoid receptor in the brain, the
very mechanism that regulates the amount of stress hormone
released by the rat’s adrenal gland.  The less maternal affection
a young rat received, the more stress hormones it produced as an
adult.

Next, Szyf administered methionine, an essential amino acid,
to the brains of the calm rats, this impacted their respective
glucocortoid receptors and they, like their neglected cousins,
became nervous wrecks!

Similarly, the McGill team reduced the levels of the same
hormones in anxious rats by pharmacologically manipulating the
same gene that produces them.  These findings have profound
implications, they suggest that similar interactions could be
used to fight depression, schizophrenia, and other brain
disorders.

Dr. Arturas Petronis M.D., PhD, Head of the Krembil Family
Epigenetics Laboratory at the University of Toronto, throw some
light on a long-standing enigma.  While DNA changes are
permanent, epigenetics modifications are in a state of flux and
generally accumulate over time.  This may explain why bipolar
disorder tends to appear at age 20 – 30 and 45 – 50.  This is due
to major hormonal changes at these ages which may in turn impact
gene regulations … via their epigenetics modifications.

The good news here is that epigenetics disorders can be
reversed making them inviting targets for new drugs.
The Future

Gradually, the evidence is accumulating and it is showing
that many genes, diseases, and environmental substances are part
of the epigenetics equation.  However, we need much more work to
be done in this area before drawing firm conclusions about the
impact of epigenetics on diseases.

Potentially, more research on epigenetics can go a long way
in curing many human diseases.  Yet, investment in this area of
study remains minuscule compared to that devoted to traditional
genetics work.  But there is a light at the end of the tunnel.

In Europe, the Human Epigenome Project was officially
launched in 2003 by the Wellcome Trust Sanger Institute,
Epigenomics AG, and the Centre Nationale de Genotypage.  The
group’s work is on DNA methylation tied to chromosomes 6, 13, 20,
and 22.  They may soon be joined by organizations in Germany and
India where research will be carried out on chromosomes 21 and X.

It’s a beginning.  But the task is enormous.  A Human
Epigenome Project will be far more complex than a Human Genome
Project.  The sooner we start, the better.  Humanity, even in the
21st century, is still affected by many diseases.

Sources

1) Backgrounder:  Epigenetics and Imprinted Genes
www.hopkinsmedicine.org/press/2002/november/epigenetics.htm

2) Epigenetics:  The Science Of Change
www.ehponline.org/members/2006/114-3/focus.html

3) Epigenetics
A new science peels away another layer of the genetic onion
by John McManamy
www.mcmanweb.com/epigenetics.html

4) McGill Reporter
McGill blazes epigenetics trail
Freeing ourselves from genetic destiny
Neale McDevitt
www.mcgill.ca/reporter/38/16/genes/

Site Search Tags:
none