[pbs] tulip color breaking
totototo at telus.net
totototo at telus.net
Mon Feb 2 14:10:33 EST 2009
On 2 Feb 2009, at 10:08, Kenneth Hixson wrote:
> Color breaking [and foliar variegation] occurs in a variety of plants, and is
> not always caused by virus.
To emphasize that point, a couple of analogous examples in other types of
organisms:
1. Indian corn with multi-colored kernels on one cob. This is the phenomenon
that inspired Barbara McClintock to do her Nobel prize-winning work on the
regulation of genetic expression.
2. An ordinary pussycat (meow!) with a coat that is partly colored, partly
white, or one that's multicolored (i.e. a calico).
While simple Mendelian genetics was a good start, as time has gone on, it's
become clear that it's not all about simple dominant and recessive alleles.
Also, extra-nuclear factors have been found to play important roles in the
expression of genes. Google "epigenetic" for further leads.
--
Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate
on beautiful Vancouver Island
http://maps.google.ca/maps?q=48.4676,-123.3262&ll=48.4676,-123.3262&z=14
More information about the pbs
mailing list