Second
generation
L
.
pennellii
introgression
lines
and
the
concept
of
bin
mapping
Liu,
Y
-
S
.
and
Zamir,
D
.
The
Hebrew
University
of
Jerusalem,
Faculty
of
Agriculture,
P
.
O
.
Box
12,
Rehovot
76100,
Israel
.
E
.
mail
zamir@agri
.
huji
.
ac
.
il
The
major
challenge
for
the
coming
years
is
to
develop
approaches
for
tying
together
sequence
information
and
biological
functions
.
One
framework
for
associating
gene
sequences
and
phenotypes
is
a
genetic
linkage
map
.
This
note
introduces
the
concept
of
bin
mapping
in
tomato
that
provides
a
rapid
method
for
assigning
a
map
position
to
DNA
sequences
.
Bin
mapping
is
based
on
an
introgression
line
(IL;
Eshed
and
Zamir
1995)
population
that
is
composed
of
L
.
esculentum
(cv
.
M82)
lines
each
containing
a
single
RFLP
defined
introgression
from
the
green
fruited
species
L
.
pennellii
(LA
716)
.
Each
of
the
ILs
is
nearly
isogenic
to
the
cultivated
tomato
and
together
the
lines
provide
complete
coverage
of
the
tomato
genome
.
The
ILs
divide
the
tomato
genome
into
bins
each
defined
by
a
unique
composition
of
genome
coverage
.
Through
probing
of
the
IL
membranes
with
DNA
probes
it
is
possible
to
associate
sequences
to
specific
bins
.
The
high
level
of
polymorphism
at
the
DNA
level
between
the
two
syntenic
species
,
L
.
esculentum
and
L
.
pennellii
,
ensures
high
mapping
efficiency
and
the
perpetual
nature
of
the
population
allows
to
accumulate
mapping
information
from
different
research
groups
into
a
single
database
.
A
unique
advantage
of
the
ILs
is
the
phenotypic
variation
that
is
unraveled
in
the
different
lines
for
simple
Mendelian
traits
as
well
as
for
QTLs
associated
with
fruit
yield
and
quality
.
In
this
communication
we
present
a
new
generation
of
the
IL
population
that
is
composed
of
75
lines
(compared
to
50
lines
in
the
previous
generation)
that
partition
the
tomato
genome
into
107
mapping
bins
.
The
original
IL
map
was
based
on
a
BC1
population
map
that
included
375
markers
while
the
new
population
is
presented
relative
to
the
F2
RFLP
map
that
includes
more
than
1500
markers
that
span
1274
cM
(Tanksley
et
al
.
1992)
.
The
orientation
of
the
second
generation
population
relative
to
the
F2
map
was
achieved
through
probing
of
all
the
lines
covering
each
of
the
chromosomes
with
all
the
markers
indicated
for
this
chromosome
on
the
genetic
map
(Figure
1)
.
A