|
Evolutionary science has long taken it for granted
that plant and animal species are genetically related to each other
the closer they are geographically. For example, two individuals
of a species of pine tree in New Jersey would be more genetically
similar when compared to each other than one of these individuals
and a pine tree in Georgia of the same species. Looking at the genetic
differences in microbes is a different story. It has been a long-standing
theory that microbes of the same species have little to no genetic
variation throughout the world and any geographic variation would
be related to climate, not genetic variation. "The motto for
microbes has been, 'Everything is everywhere, but the environment
selects,' " explains John Taylor, professor of plant and microbial
biology at UC Berkeley's College of Natural Resources.
Looking at this "motto," Rachel Whitaker, a graduate student
in Taylor's lab traveled to hot springs around the world, taking
samples of a specific species of a microbe, Sulfolobus islandicus,
as well as looking at existing samples taken from similar sites.
The research indicated that the separate cultures had very small,
but significant genetic differences between populations living in
different geographic regions. "If this type of geographic pattern
occurs in other microbes, it means the microbial world is even more
diverse than we had previously predicted, which is astounding,"
expounded Whitaker.
The implications this study might have on how scientists examine
pathogens could be significant. A slight genetic variation could
mean the difference between a workable cure and a complete dud.
Species of the same pathogen often emerge in different parts of
the world and the knowledge that these microbes could vary genetically
inside of the same species could be invaluable as researchers develop
more specific treatments.
|
