<<<No. Some of us 47ers can be tetrochromats.
Hah, as an endocrinologist I was clearly remiss in not specifying
"essentially impossible" for normal males. Almost all Klinefelter's patient
are infertile w/o heroic efforts and as you have daughters
I think you would be evicted from the 47 ers club. Unlike in in women,
patients with Klinefelter's syndrome do no have nearly random X inactivation.
60% of the time the disorder is from 2 maternal X's and the remainder obviously
one X from each parent.
Still there is differential inactivation so that 80% of one copy of the X is
inactivated--so that leaves only 20% dose of anomalous opson gene to enable
enhance color perception. That seem quite unlikely to be enough, but not
impossible. I have had a few Klinefelter mosaics that have a very mild
phenotype and can be fertile as well.
Then there are always chimeras --no clue about pattern of X inactivation in
them.
(Curiously the rest of the visual system seems to be able to take advantage of
the additional signal when present if the cone is different enough.)
Let's modify the odds to very very very unlikely, Mike
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|