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Recently
the media published the draft sequence of the human genome. Some dubbed the
publication of this information as "the biggest news event in the past 50
years of science" and it certainly was an amazing achievement.
The genome project has been hailed as a "breakthrough" and a
"revolution", but some people have questioned whether the knowledge
may be used for evil as much as for good. Just as splitting the atom provided
access to bombs or power-stations, access to the human genome may give some
people a new tool for progress or a weapon for destruction.
Most of the media reports said that humans are not as complex as at first
thought, with only about 35,000 genes. Previous estimates had been as high as
140,000. It turns out that humans have about the same number of genes as an ear
of corn, or twice as many as a fly.
It is true that humans have far fewer genes than expected, but it is not true
that humans are "not much more complicated than baker's yeast". Why?
Because it used to be thought that, for the most part, each gene contained the
instruction code for building one specific protein (i.e. a specific structural
component of the cell), but now the mystery is how do a mere 35,000 genes direct
the production of the hundreds of thousands of components that make up the whole
human body?
Instead of simplifying matters, the genome project has shown that things are far
more complicated than anyone imagined.
The hidden complexity seems to be found in the way genes are 'read' or
'unravelled'. To illustrate this, take the way sentences can be strung together
with only a limited number of words. Take the sentence you just read. If you
switched a few words round, or swapped them for others, the sentence would
become nonsense. In the same way, the sequences in the genes must be written in
exactly the right sequence in order to produce the thousands of different
'meanings'.
Another illustration of this is the way a similar set of instructions can be
used to explain how to operate a CD player, a radio, a television and a DVD
player. Similar words but a different sequence gives a totally different result.
The genetic researchers now start the really hard work - mapping the sequences
and relating these sequences to the products.
There are some who claim that human DNA contains "junk". They say
that 98% of human DNA has no function, and they label it as "evolutionary
junk", left over from millions of years of development. However, as
'Science' (G.Vogel Science 291 (5507):1184,2001) says :
"scientists have discovered many riches hidden in the junk, and . . .
several researchers predict that some of the most intriguing discoveries may
come from areas once written off as genetic wastelands."
It is premature to claim that any DNA is "junk" because 1. the
investigation has just begun, 2. In the past, many initial conclusions by
scientists have had to be completely reversed, 3. If there really was 'junk' it
would probably cause the DNA to fall apart.
From the Christian point of view, the complexity and exact sequencing of DNA, and the efficient operation of genes is directly related to the Biblical teaching of a Creator. It seems reasonable to me that the DNA should bear similarities with all other DNA in all other living things, because it is logical and efficient to base all life on one planet on the same basic components. Just as we never question a car-manufacturer for his use of the same components, modified to produce different models, why should we assume that God has to produce life by a dissimilar method?