Abstract
Genetics have come a long way
from the days of Gregor Mendel,
when a gene was considered an information-
containing element of
unknown chemical nature that gave
rise to an observable trait such as
Mendel's experiments with round or
wrinkled peas. Working with pea
plants, Mendel discovered the fundamental
principles of heredity in the
1860s. Clearly, regulation of gene
expression is a major key to development.
Discovering the genetic underpinnings
for this dramatic transformation
is a major challenge of
biology today.
We are now in an era of biological
discovery of unprecedented excitement
and achievement. Genetic information
is expressed by its translation
into proteins of specific structure and
function which , in turn , brings about
an organism 's phenotype (the expressed
traits).
Mutagenesis, the creation of mutations,
can occur in a number of ways
as the cells res pirate, repair, and
recombine. This can lead to base-pairs
of subst itutio ns, insertions or deletions.
Si nce determining how genes
are translated into proteins in the
1960s, scienti ts can give a description
of inheritable changes that arise.
The DNA (deoxyribo nucleic acid)
inh erited by an organism, controls
the activity of each cell by specifying
the sy nth esis of enzymes and other
proteins. A gene does not build a protein
directly but, instead, dispatches
instructions in the form of R A
(ribonucleic acid) which , in turn , programs
protein synthesis. Cells are governed
by a chain of command: D A -
RNA - protein. The scheme is known
as the " Central Dogma of Molecular
Biology;· a term coined by Francis
Crick .