Gregor Johann Mendel on Pisum sativum. A centennial


Mark, H.H.; Mendel, G.J.

Archives of Ophthalmology 76(2): 287-289

1966


In the one hundred years since Gregor Johann Menders paper "Versuche ueber Pflanzenhybriden" (Experiments in Plant Hybrids) appeared in the Verhandlungen des Naturforschenden Vereins in Brünn (4:3, 1866), the impact of scientific genetics on our daily life has been truly immeasurable. The meat on our table now comes from carefully bred livestock, our bread front genetically improved grain. In ophthalmology the known number of ocular disorders has been steadily growing, and, as knowledge of their fundamental mechanisms deepens, so does the realization that many are genetically determined, whether the disorder be color blindness or retinoblastoma, myopia or homocystinuria. Therapeutic progress has placed many of the traumatic and infectious diseases in the background, while at the same time the focus of interest has been turned on degenerative and hereditary disorders.

281
Our
Ophthalmic
Heritage
Edited
by
Charles
Snyder
Lucien
Howe
Library
of
Ophthalmology,
243
Charles
St,
Boston
02114
Gregor
Johann
Mendel
on
Pisum
sativum
A
Centennial
HARRY
H.
MARK,
MD,
New
Haven,
Conn
In
the
one
hundred
years
since
Gregor
Johann
Menders
paper
"Versuche
ueber
Pflanzenhybriden"
(Experiments
in
Plant
Hybrids)
appeared
in
the
Verhandlungen
des
Naturforschenden
Vereins
in
Briinn
(4:3,
1866),
the
impact
of
scientific
ge-
netics
on
our
daily
life
has
been
truly
im-
measurable.
The
meat
on
our
table
now
comes
from
carefully
bred
livestock,
our
bread
front
genetically
improved
grain.
In
ophthalmology
the
known
number
of
ocular
disorders
has
been
steadily
grow-
ing,
and,
as
knowledge
of
their
funda-
mental
mechanisms
deepens,
so
does
the
realization
that
many
are
genetically
de-
termined,
whether
the
disorder
be
color
blindness
or
retinoblastoma,
myopia
or
homocystinuria.
Therapeutic
progress
has
placed
many
of
the
traumatic
and
in-
fectious
diseases
in
the
background,
while
at
the
same
time
the
focus
of
interest
has
Gregor
Johann
Mendel
(from
Iltis,
H.:
Gregor
Johann
Mendel,
Berlin
:
Springer
been
turned
on
degenerative
and
heredi-
Verlag,
1924).
tary
disorders.
Life
for
Gregor
Johann
Mendel
was
mainly
a
long
chain
of
disappointments,
seldom
paralleled
in
the
biography
of
science.
Yet
the
belated
discovery
of
his
work
is,
in
fact,
a
highly
dramatic
episode
—which
may
console
many
a
frustrated
thinker
longing
for
acclaim.
He
was
born
Johann
Mendel
on
July
20,
1822,
in
the
small
village
of
Heinzen-
dorf,
Silesia,
then
a
province
of
the
Austro-Hungarian
Empire.
His
parents
were
peasants
of
little
means;
the
father
had
to
work
three
days
a
week
for
Countess
Reprint
requests
to
2
Church
St
South,
New
Haven,
Conn
06519.
Arch
0
phthal—Vol
76,
Aug
1966
288
OUR
OPHTHALMIC
HERITAGE—SNYDER
Waldburg,
as
prescribed
by
the
old
feudal
law.
Under
such
dire
fi
nancial
circum-
stances
Johann's
endeavor
to
obtain
higher
education
was
greatly
embarrassed.
Upon
graduation
from
elementary
school
Mendel
attended
high
school
in
Leip-
nik,
and
graduated
from
the
Gymnasium
in
Tropau
at
the
age
of
18.
What
little
money
he
received
from
his
family
was
scarcely
enough
to
keep
body
and
soul
to-
gether,
so
that
he
always
had
to
add
to
it
by
private
teaching.
Sickness,
too,
inter-
rupted
his
learning.
He
was
fi
nally
accepted
at
the
Philosophical
Institute
in
Olmiitz,
Moravia,
the
same
town
where,
much
later,
the
fi
rst
successful
penetrating
kerato-
plasty
was to
be
performed.
After
two
years
there,
Mendel
contemplated
his
future
and
could
see
no
way
toward
a
satisfactory
worldly
existence
compatible
with
his
intellectual
ideals.
A
devout
Catholic,
he,
therefore,
entered
the
Augustinian
monas-
tery
of
St.
Thomas
in
Briinn,
and
took
the
name
Gregor.
For
four
years
Gregor
Mendel
applied
himself
to
the
study
of
theology.
He
had
only
occasional
moments
to
indulge
in
his
favorite
subject
—the
natural
sciences.
He
was
ordained
a
priest
at
25.
As
a
parish
priest,
he
did
poorly,
for
the
sight
of
suf-
fering
made
him
ill.
He
turned
to
teaching
again,
and
took
the
official
examination
for
teachers
in
natural
science.
He
failed
to
pass.
With
the
help
of
friends
he
was,
nevertheless,
admitted
to
the
University
of
Vienna.
For
two
years
he
attended
lec-
tures
in
physics
(under
Doppler),
chemistry,
mathematics,
geology,
botany,
and
microscopy.
But
when
the
time
came
for
his
examination,
Mendel
failed
again.
At
the
dead
end
of
his
academic
street,
he
returned
to
Briinn
and
to
teaching
in
the
local
school.
Anyone
else
would
have
thrown
up
his
hands
in
despair
and
retreated
into
a
shell,
but
not
Mendel.
It
was
during
these
fi
rst
years
back
in
Br
-
arm
that
he
con-
ducted
his
now
famous
experiments
with
the
garden
pea
(Pisunt
satieum).
Based
on
observations
of
over
10,000
hybrids
and
355
artificial
pollinations,
Mendel
derived
the
rules
and
the
mathematical
formula
that
explain
hereditary
transmis-
sion.
In
its
simplest
form
it
may
be
expressed
in
Newton's
binomial
theorem
:
(a
+
b)
2
=
a
2
+
2ab
+
b
2
,
or:
one
half
of
the
progeny
(2ab)
breeds
true
to
the
paternal
characters,
while
the
other
will
be
divided
equally
between
dominant
(a)
and
recessive
(b)
characters.
Surprising
as
it
may
seem
in
retrospect,
Mendel's
paper
at
the
time
received
no
attention
whatsoever.
Research
has
shown
that
it
was
available
in
many
univer-
sity
libraries
in
Europe
and
America,
but
was
obviously
little
read.
Gregor
Mendel
continued
his
work
in
the
monastery.
Two
years
after
the
pub-
lication
of
his
paper
he
was
elected
abbot,
and
became
so
involved
in
administrative
work
that
little
opportunity
arose
for
creative
thinking.
He
died
on
the
morning
of
Jan
6,
1884,
of
chronic
nephritis
with
heart
failure.
All
the
while,
work
in
the
fi
eld
of
heredity
continued.
Finally
in
1900,
three
workers,
each
independent
of
the
other,
discovered
a
numerically
calculable
combi-
nation
in
the
progeny
of
hybrids.
The
Dutch
botanist
Hugo
de
Vries,
speculating
on
a
theory
of
evolution
by
jumps,
was
working
with
plant
mutations
when
he
found
the
regularity
in
the
hybrids.
He
published
his
report
in
March
1900,
completely
omitting
Mendel's
name,
but
using
Mendel's
terms
"dominant"
and
"recessive."
In
Tubingen,
at
the
same
time,
Carl
Correns
was
putting
the
fi
nishing
touches
to
his
essay
on
heredity
in
which
he,
too,
arrived
at
the
rule
of
progeny.
When
he
saw
de
Vries's
paper
he
quickly
sent
his
own
to
the
editor
(April
1900).
Correns
was
the
fi
rst
to
give
the
designation
"Mendelian
laws"
to
Mendel's
crossing
results,
and
added
that
.
.
.
the
same
thing
happened
to
me
which
now
seems
to
be
happening
to
de
Vries:
I
thought
that
I
had
found
something
new.
But
then
I
convinced
myself
that
the
abbot
Gregor
Mendel
in
Arch
Ophthal—Vol
76,
Aug
1966
OUR
OPHTHALMIC
HERITAGE—SNYDER
289
Briinn,
had,
during
the
sixties,
not
only
obtained
the
same
results
through
extensive
experiments
with
peas,
which
lasted
for
many
years,
as
did
de
Vries
and
I,
but
has
also
given
exactly
the
same
explanation,
as
far
as
that
was
possible
in
1866.
Also
working
with
peas,
for
a
postgraduate
research
thesis,
was
Erich
Tscher-
mak
in
Vienna.
He
discovered
Mendel's
name
referred
to
in
one
widely
read
book
on
heredity,
and
obtained
Mendel's
original
paper
from
the
library.
"There
1
read
to
my
great
surprise
that
Mendel
had
already
carried
out
such
experiments
much
more
extensive
than
mine,
had
noted
the
same
regularities,
and
had
already
given
the
explanation
for
the
3:1
segregation
ratio."
Tschermak
was
even
more
horrified
when
a
few
months
later
he
received
reprints
of
de
Vries's
and
Correns's
papers.
He
looked
for
a
publisher
for
his
own
work,
and
fi
nally
found
one
in
the
editor
of
an
agricultural
magazine
(June
1900).
It
was
at
this
point
that
the
systematic
study
of
genetics
as
we
know
it
today
really
began,
34
years
later
than
it
could
have.
So
fruitful
has
it
become,
that
Mendel's
name
is
known
to
every
school
child.
Of
the
three
workers
only
Hugo
de
Vries
remained
disappointed:
he
avoided
mention
of
Mendel's
name
in
his
book
on
plant
breeding
(1907),
and
refused
to
sign
a
petition
for
the
erection
of
a
Mendel
memorial
in
Briinn.
The
once
forgotten
Augustinian
monk
would
not
have
minded,
for
he
knew,
as
one
of
his
students
overheard
him
say,
that
"my
time
will
surely
come."
Arch
°Athol
—Vol
76,
Aug
1966