Introduction

It’s hard to believe that only some 60 odd years have gone
by since Watson and Crick introduced humanity to the double
helix.  Today, terms like genes, DNA, RNA, genetic mutations,
genetic (inherited) diseases and so on are common currency.  Most
of us know what they mean.  Indeed, the time came when the
scientific world asked itself the question:  Can we map the human
genome?  Can we determine what all the letters of this intriguing
universe are?

The human genome project began in 1990 and was initiated by
the U.S. Department of Energy and the National institutes of
Health.  My understanding is that this was a worldwide effort
with many countries entrusted with the task of decoding and
recording a part of the genome.  It was expected to take 15
years, instead it was completed in 13 years.  A rare example of a
project that finished ahead of time!

When the dust settled, the 3 billion chemical base pairs
that make up the human DNA were identified and stored in
databases to be used by the scientific world.  The result?  A
whole bunch of the 4 bases:  A,C,G,T (more on that in a
subsequent section).  The whole thing really was an endless
procession of these 4 letters.  It doesn’t make for exciting
reading unless you’re engaged in genetic research.

Ultimately, some 30,000 genes were identified (we expected
some 100,000 genes).  Only a small portion codes for proteins,
the rest was considered as “junk” DNA.

The project was extended to nonhuman organisms:  Human gut
bacterium Escherichia Coli, the fruit fly, and the laboratory
mouse.  I believe that the genetic coding for many more organisms
was subsequently mapped out.  All in all, a tremendous
achievement for humankind.

So was it time to crack open the champagne?  To be sure we
can and should celebrate as long as we keep in mind that a
tremendous amount of work is still left to identify and determine
the functions of the proteins coded by the genetic machinery.
This will take us decades if not centuries.  Fine, but then will
we have reached the summit of the mountain?  Not by a long shot!
Enter epigenetics.

I have heard of epigenetics some 25 years ago.  The term
itself has been around for close to a century.  Serious work was
carried out for some 30 years by a handful of scientists only.
Most of the scientific community scoffed at the notion that our
genetic destiny was not hardwired into our DNA.  (One of the
early pioneer, Dr. Moshe Szyf of McGill University in Montreal
likened epigenetics to software:  a gene could have as many as
700 epigenetic programs!)  During the last 8 years, however,
epigenetics is finally getting the attention it deserves; work is
carried out across the world.  For me this is great news, for I
have always been fascinated by the intriguing possibilities of
this area of science, but otherwise had little information to
satisfy my curiosity.  There is now more data on epigenetics,
enough to share some of it with you in this article.  (The
material for this writing, if you want to delve further, was
obtained by going on Google and entering:  Epigenetics, and
Epigenetics in Plants.  Needless to say, you can enter such
search terms as Epigenetics and Cancer, Epigenetics and
Addiction, and so on).

Keep in mind that this is only a bird’s eyeview of
epigenetics.  I would not want to vouch for the total accuracy of
what is presented.  I am simply sharing the fruits of my
research.  It is certainly incomplete; for example, there is so
much more to say on the connection between epigenetics,
lifestyles, and environment.  The point I am making is this:
Research further if a specific topic is of interest to you.

A few more points:  I did not attempt to break the subject
into clearly delineated sections; that would have been impossible
considering the complexity of the topic and the fact that this is
a new area of science.  Also, there is overlap and repetitions.
This after all is the presentation of the different facets of one
subject:  Epigenetics.

I have kept my article as simple as possible; I believe it’s
accessible to the average person.  Do not let big words such as
Methylation, Imprinting, Histones, Chromatin Structure, Silencing
of Genes, etc., scare you.  Everything is, I believe, simply
explained.  (If I can understand it and write about it with an
accounting background, so can you!)

I have included a part on the biological aspects of our
genome.  (The Dance of Life:  Sections IV, V, and VI)  Those of
you with a solid biology background will probably not need it.
On the other hand, those of you totally lacking such knowledge
may have difficulty following it.  It is fascinating, but it is
not essential to understand the rest of the article.  Therefore,
feel free to skip it.

Finally, I close the article by providing you with my own
assumptions.  It brings the whole thing down to earth.  I suspect
you will also have your own views on the subject.

With this introduction out of the way, I am explaining next
some essential concepts before moving on to the various parts.

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