Re: HYB: pink probabilities

I never have been able to understand why probability of pink from one
tttt parent and one TTtt parent is 1/6 instead of 1/4 (which is what a
simple 4 x 4 Punnett square tells me).

4t across one side, ttTT down the other gives 16 squares, & four of them
are tttt.

Ignoring other factors for the time being (i.e., genes that would color
over the pink, hiding it with anthocyanin, or inhibitors, or wrong
yellow pigment genes, & whatever).

I can't get a denominator of "6" no matter how cross-eyed I look at this
.... what am I missing here?

I ran into this stumbling block before and got stuck.  Seems like it is
'explained' in TWOI but I couldn't figure it out, mostly because I
couldn't visualize what was going on in terms of offspring.  Maybe now
that I've made a few non-pink crosses and gotten a few pinks, I might
understand if anybody has time & patience to try...

3+ inches of rain in the bucket, a break today, then more over the
weekend.  Glub.
--
Linda Mann east Tennessee USA zone 7/8
East Tennessee Iris Society <http://www.korrnet.org/etis>
American Iris Society web site <http://www.irises.org>
talk archives: <http://www.hort.net/lists/iris-talk/>
photos archives: <http://www.hort.net/lists/iris-photos/>
online R&I <http://www.irisregister.com>

---------------------------------------------------------------------
To sign-off this list, send email to majordomo@hort.net with the
message text UNSUBSCRIBE IRIS
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index