The existence of life without reproduction is the subject of some
speculation. The biological study of how the origin of life led from
non-reproducing elements to reproducing organisms is called abiogenesis.
Whether or not there were several independent abiogenetic events,
biologists believe that the last universal ancestor to all present life
on earth lived about 3.5 billion years ago.
Today, some scientists have speculated about the possibility of creating
life non-reproductively in the laboratory. Several scientists have
succeeded in producing simple viruses from entirely non-living
materials. The virus is often regarded as not alive. Being nothing more
than a bit of RNA or DNA in a protein capsule, they have no metabolism
and can only replicate with the assistance of a hijacked cell's
metabolic machinery.
The production of a truly living organism (e.g., a simple bacterium)
with no ancestors would be a much more complex task, but may well be
possible to some degree according to current biological knowledge. A
synthetic genome has been transferred into an existing bacterium where
it replaced the native DNA, resulting in the artificial production of a
new M. mycoides organism.
There
is some debate within the scientific community over whether this cell
can be considered completely synthetic on the grounds that the
chemically synthesized genome was an almost 1:1 copy of a naturally
occurring genome and, the recipient cell was a naturally occurring
bacterium. The Craig Venter Institute maintains the term "synthetic bacterial cell" but they also clarify "...we do not consider this to be "creating life from scratch" but rather we are creating new life out of already existing life using synthetic DNA." Venter
plans to patent his experimental cells, stating that "they are pretty
clearly human inventions". Its creators suggests that building 'synthetic life'
would allow researchers to learn about life by building it, rather than
by tearing it apart. They also propose to stretch the boundaries
between life and machines until the two overlap to yield "truly programmable organisms."Researchers
involved stated that the creation of "true synthetic biochemical life"
is relatively close in reach with current technology and cheap compared
to the effort needed to place man on the Moon.
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