HYB: Gene Color Chart

Steve Rocha wrote:

:   An example is a cross between a red self x pink self.
:  Does the dominant  I  overide the V and the PL ? Another question is h=
ow
:  many xxx's does the offspring end up with? On the chart there are 5 fo=
r
the
:  red and 3 for the pink. Which 4 genes do they end up with?

Tom's chart is a convenient tool, a great way of showing the interactions=

of various genes, but it's just one step in the process.  You can use it =
to
estimate the genes carried by each of the parents, but then you still hav=
e
to examine the permutations and combinations to predict the variety and
frequency of genotypes & karotypes among the offsping.  =


For the red parent, the visible violet tells us that it is Vvvv, VVvv,
VVVv, or VVVV; and iiii. Information about the presence or absence of the=

PL is obscured.

For the pink parent, if we assume pink self rather than pink glaciata --
information about the presence or absence of V is obscured, as is
information about PL.  The presence of at least one I is assumed, so that=

it may be Iiii, IIii, IIIi, or IIII.

That's the easy part.  Now comes the recombinant analysis.  I can simplif=
y
matters considerably if I skip the statistics and Punnett square and just=

look at the possibilities. =


For violet, the red parent can contribute VV, Vv, or vv.  The pink parent=
's
contribution is unknown, so it's designated xx.  That means seedlings can=

be VVxx, Vvxx or vvxx.  Some will show violet.  All may show violet.  It
depends on what those "xx" genes really are.

For the inhibitor, the red parent can contribute only ii.  The pink paren=
t
could contribute II, Ii, or ii.  The offspring could thus be IIii, Iiii, =
or
iiii.  Some of these theoretical seedlings will have their violet
inhibited, others won't.

For the plicata, we know NOTHING.  We can't predict the occurence of one
among the seedlings, but we can't rule it out either.

Dare I mention that we can't predict what the seedlings will actually loo=
k
like without analyzing the carotene/lycopene pathways, too?  For example,=

it's quite possible to cross a red self with a pink self and get a
yellow-ground plicata....

Sharon McAllister (73372.1745@compuserve.com)
Who understands why a lot of people just wait to see what their seedlings=

will look like
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index